OFFICE LEASE

                             PACIFIC TELESIS CENTER
                                  TELESIS TOWER
                            San Francisco, California

                                    LANDLORD:

                           POST-MONTGOMERY ASSOCIATES

                                     TENANT:

                           CHARLES SCHWAB & CO., INC.

                                 October 4, 1996

<PAGE>   2
                                TABLE OF CONTENTS

                                                                        PAGE

1.  Definitions....................................................        1
         1.1.  Terms Defined.......................................        1
         1.2.  Basic Lease Information.............................       26
         1.3.  Effect of Certain Defined Terms.....................       26

2.  Lease of Premises..............................................       27
         2.1.  Premises............................................       27
         2.2.  Antenna and Antenna Area............................       28
         2.3.  Lease for Generator Area............................       37
         2.4.  Expansion of Premises...............................       41
         2.5.  Notice Right with Respect to Certain Floors.........       50
         2.6.  Limited Right of Termination with Respect to
               Certain Floors......................................       50
         2.7.  Right of Termination with Respect to Floor 2
               Galleria............................................       53

3.  Term ..........................................................       54
         3.1.  Condition and Acceptance of Premises................       54
         3.2.  Extension...........................................       60

4.  Rent ..........................................................       67
         4.1.  Obligation to Pay Rent..............................       67
         4.2.  Manner of Payment of Rent and Additional Charges....       69
         4.3.  Additional Charges..................................       70
         4.4.  Late Payment of Rent and Additional Charges;
               Interest............................................       70
         4.5.  Free Rent...........................................       71

5.  Calculation and Payments of Escalation Charges.................       73
         5.1.  Payment of Estimated Escalation Charges.............       73
         5.2.  Escalation Charges Statement and Adjustment.........       74
         5.3.  Proration for Partial Year..........................       76
         5.4.  Tenant Audit Rights With Respect to Escalation
               Charges.............................................       76
         5.5.  Certain Limitations With Respect to Estimates
               of Escalation Charges...............................       80
         5.6.  Certain Limitations on Real Estate Taxes; Contest
               of Real Estate Taxes; Contest of Impositions........       81
         5.7.  Adjustment of Base Year Operating Expenses
               for Certain Insurance Items.........................       84

                                    TOC - I
<PAGE>   3
         5.8.  Dispute Resolution..................................       85

6.  Impositions Payable by Tenant..................................       85

7.  Use of Premises................................................       86
         7.1.  Permitted Use.......................................       86
         7.2.  No Violation of Legal and Insurance Requirements....       87
         7.3.  Compliance with Legal, Insurance and Life Safety
               Requirements........................................       89
         7.4.  No Nuisance.........................................       90
         7.5.  Compliance With Environmental Laws; Use of
               Hazardous Materials.................................       90
         7.6.  Cost of Handicap Access and Life-Safety Code
               Compliance..........................................       91

8.  Building Services..............................................       92
         8.1.  Maintenance of Complex..............................       93
         8.2.  Building Standard Services..........................       94
         8.3.  Interruption or Unavailability of Services;
               Abatement of Rent and Additional Charges............       95
         8.4.  Tenant's Use of Excess Electricity, Water, and
               Heating, Ventilation and Air-Conditioning...........       97
         8.5.  Provision of Additional Services....................       99
         8.6.  Standards With Respect to Certain Services..........       99
         8.7.  Compliance With Environmental Laws; Use of
               Hazardous Materials.................................      102

9.  Maintenance of Premises........................................      104

10.  Alterations to Premises.......................................      105
         10.1.  Landlord Consent; Procedure........................      105
         10.2.  General Requirements...............................      107
         10.3.  Ownership and Removal of Alterations...............      109
         10.4.  Landlord's Construction Allowance..................      111
         10.5.  Right of Tenant to Make Certain Alterations to
                Complex............................................      119

11.  Liens.........................................................      120

12.  Damage or Destruction.........................................      120
         12.1.  Duration of Repair.................................      120
         12.2.  Obligation to Repair...............................      122
         12.3.  Election on Certain Events.........................      123
         12.4.  Cost of Repairs....................................      125

                                    TOC - II
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         12.5.  Damage at End of Term..............................      125
         12.6.  Proration of Rent and Additional Charges on
                Termination........................................      126
         12.7.  Waiver of Statutes.................................      126

13.  Eminent Domain................................................      126
         13.1.  Effect of Taking...................................      126
         13.2.  Condemnation Proceeds..............................      128
         13.3.  Restoration of Premises and Complex................      128
         13.4.  Tenant Waiver......................................      129

14.  Insurance.....................................................      129
         14.1.  Liability Insurance................................      129
         14.2.  Landlord Casualty Insurance........................      130
         14.3.  Tenant Casualty Insurance..........................      130
         14.4.  Form of Policies...................................      131
         14.5.  Tenant Right of Self-Insurance.....................      132

15.  Waiver of Claims and Subrogation Rights.......................      132

16.  Waiver of Liability and Indemnification.......................      133
         16.1.  Waiver and Release.................................      133
         16.2.  Indemnification of Landlord........................      133
         16.3.  Indemnification of Tenant..........................      135

17.  Assignment and Subletting.....................................      136
         17.1.  Compliance Required................................      136
         17.2.  Request by Tenant; Landlord Response...............      136
         17.3.  Conditions for Landlord Approval...................      139
         17.4.  Costs and Expenses.................................      140
         17.5.  Payment of Excess Rent and Other Consideration.....      140
         17.6.  Assumption of Obligations; Further Restrictions
                on Subletting......................................      141
         17.7.  No Release.........................................      142
         17.8.  No Encumbrance.....................................      143
         17.9.  Certain Rights with Respect to Assignments and
                Subleases..........................................      143

18.  Rules and Regulations.........................................      146

19.  Entry of Premises by Landlord.................................      146
         19.1.  Right to Enter.....................................      146
         19.2.  Certain Secure Areas; Cooperation with Tenant
                Security Personnel.................................      148

                                   TOC - III
<PAGE>   5
         19.3.  Tenant Waiver of Claims............................      149
         19.4.  Scope of Emergencies...............................      150

20.  Default and Remedies..........................................      150
         20.1.  Events of Default..................................      150
         20.2.  Notice to Tenant...................................      152
         20.3.  Remedies Upon Occurrence of Default................      153
         20.4.  Damages Upon Termination...........................      153
         20.5.  Landlord's Right to Cure Defaults..................      154
         20.6.  Waiver of Forfeiture...............................      154
         20.7.  Landlord Default; Tenant's Right to Cure
                Landlord Default...................................      155
         20.8.  Remedies Cumulative................................      156

21.  Subordination, Attornment and Non-disturbance.................      157
         21.1.  Landlord Right to Encumber; Subordination and
                Attornment.........................................      157
         21.2.  Non-disturbance....................................      158
         21.3.  No Superior Encumbrances...........................      159

22.  Sale or Transfer by Landlord; Lease Non-Recourse..............      159
         22.1.  Release of Landlord on Transfer....................      159
         22.2.  Lease Non-recourse to Landlord.....................      160

23.  Estoppel Certificate..........................................      162
         23.1.  Tenant's Certificate...............................      162
         23.2.  Landlord's Certificate.............................      163
         23.3.  Effect of Certificate..............................      163

24.  No Light, Air, or View Easement...............................      164

25.  Holding Over..................................................      165

26.  Waiver........................................................      165

27.  Notices.......................................................      166

28.  Authority; Tenant Financial Information; Confidentiality......      167
         28.1.  Authority..........................................      167
         28.2.  Tenant Financial Information; Confidentiality......      167

29.  Parking.......................................................      168

30.  Signage.......................................................      169

                                    TOC - IV
<PAGE>   6
31.  Miscellaneous.................................................      171
         31.1.   No Joint Venture..................................      171
         31.2.   Successors and Assigns............................      171
         31.3.   Construction and Interpretation...................      171
         31.4.   Severability......................................      172
         31.5.   Entire Agreement; Amendments......................      172
         31.6.   Governing Law.....................................      173
         31.7.   Litigation Expenses...............................      173
         31.8.   Standards of Performance and Approvals............      173
         31.9.   Brokers...........................................      174
         31.10.  Memorandum of Lease...............................      175
         31.11.  Quiet Enjoyment...................................      175
         31.12.  Surrender of Premises.............................      175
         31.13.  Building Directory................................      176
         31.14.  Name of Building; Address.........................      176
         31.15.  Exhibits..........................................      176
         31.16.  Arbitration of Fair Market Rent and Fair Market
                 Renewal Rent......................................      176
         31.17.  Arbitration of Dispute............................      178
         31.18.  Survival of Obligations...........................      181
         31.19.  Time of the Essence...............................      181

                                     TOC - V
<PAGE>   7
                                  OFFICE LEASE

                             PACIFIC TELESIS CENTER
                                  TELESIS TOWER
                            San Francisco, California

BASIC LEASE INFORMATION

Lease Date:                         October 4, 1996

Landlord:                           Post-Montgomery Associates,
                                    a California general partnership, consisting
                                    of The Prudential Insurance Company of
                                    America, and NLI Properties West, Inc.

Landlord's Address:                 One Montgomery Street, Suite 1300
                                    San Francisco, California  94104
                                    Attn:  General Manager

                                    With a copy to:

                                    Cassidy & Verges
                                    20 California Street, Suite 500
                                    San Francisco, California  94111
                                    Attn:  Stephen K. Cassidy, Esq.

Tenant:                             Charles Schwab & Co., Inc.,
                                    a California corporation

Tenant's Address:                   101 Montgomery Street
                                    San Francisco, California 94104
                                    Attn:  Vice President,
                                           Corporate Services

                                    With copies to:
                                    P.O. Box 881566
                                    c/o Corporate Real Estate Lease
                                    Administration
                                    San Francisco, California  94188-1566


                                       i
<PAGE>   8
                                            and

                                    Charles Schwab & Co., Inc.
                                    101 Montgomery Street
                                    San Francisco, California  94104
                                    Attn:  Mary B. Templeton, Esq.
                                           General Counsel

                                           and

                                    Corbin Silverman & Sanseverino
                                    805 Third Avenue
                                    New York, New York  10022
                                    Attn:  Raymond A. Sanseverino, Esq.

Premises:                           15,805 feet of Galleria Rentable Area
                                    located on Floor 2 (also designated as Level
                                    3 of the Galleria and referred to in this
                                    Lease as "Floor 2 Building") as shown by the
                                    hatching on the Floor Plan attached as
                                    Exhibit A-1; the Rentable Area of Floor 3 as
                                    shown by the hatching on the Floor Plan
                                    attached as Exhibit A-2; and the entire
                                    Rentable Area of - Floors 4, 5, 6, 7, 8, 9,
                                    10, 11, 12, 13, 14, 17, 18, 19, 20 and 21,
                                    as shown on the Floor Plans attached as
                                    Exhibit A-2 through A-18, respectively; and
                                    1,347 feet of Galleria Rentable Area on
                                    Floor 2 (also designated as Level 3 of the
                                    Galleria and referred to in this Lease as
                                    "Floor 2 Galleria") as shown by the hatching
                                    on the Floor Plan attached as Exhibit A-19.

Base Year:                          For each Floor or partial Floor of the
                                    Premises (other than Floor 2 which has no
                                    Base Year), the calendar year in which the
                                    Delivery Date (as determined pursuant to
                                    Section 3.1 below) for such Floor shall
                                    occur, except that if a Delivery Date shall
                                    occur on or after October 1 of a calendar
                                    year, then the Base Year for the affected
                                    Floor shall be the next calendar year.


                                      -ii-
<PAGE>   9
Expansion
Premises:



================================================================================
 Floor                    Rentable Area              Tenant's Percentage Share
- --------------------------------------------------------------------------------
                                                         
  15                         18,607                             2.83%
- --------------------------------------------------------------------------------
  16                         18,625                             2.84%
- --------------------------------------------------------------------------------
  22                         18,923                             2.88%
- --------------------------------------------------------------------------------
  23                         18,923                             2.88%
- --------------------------------------------------------------------------------
  24                         18,923                             2.88%
- --------------------------------------------------------------------------------
  25                         18,923                             2.88%
================================================================================


Extended Terms:                     Two (2) periods of five (5) years each.

Floor, Rentable Area, Delivery Dates, Expiration Dates, Base Rent and Tenant's
Percentage Share:



=========================================================================================================================
                                                                                      Base Rent                 Tenant's
               Rentable                                                   ----------------------------------   Percentage
   Floor         Area       Delivery Date         Expiration Date          Years 1-5           Years 6 -         Share
                                                                            of Term         Expiration Date
                                                                                                of Term
- -------------------------------------------------------------------------------------------------------------------------
                                                                                              
     2           1,347    December 18, 1999      December 31, 2011         $32,328.00         $36,705.75          1.54%
 Galleria
- -------------------------------------------------------------------------------------------------------------------------
     2          15,805    December 18, 1999      December 31, 2011        $189,660.00        $241,026.25         18.04%
 Building
- -------------------------------------------------------------------------------------------------------------------------
     3           5,892    December 18, 2000      December 31, 2011        $141,408.00        $160,557.00          0.90%
- -------------------------------------------------------------------------------------------------------------------------
     4          18,590    April 1, 2001          December 31, 2011        $446,160.00        $506,577.50          2.83%
- -------------------------------------------------------------------------------------------------------------------------
     5          18,590    April 1, 2001          December 31, 2011        $446,160.00        $506,577.50          2.83%
- -------------------------------------------------------------------------------------------------------------------------
     6          18,590    April 1, 2001          December 31, 2011        $446,160.00        $506,577.50          2.83%
- -------------------------------------------------------------------------------------------------------------------------
     7          18,590    January 1, 2000        December 31, 2011        $446,160.00        $506,577.50          2.83%
- -------------------------------------------------------------------------------------------------------------------------
     8          18,590    July 1, 2001           December 31, 2011        $446,160.00        $506,577.50          2.83%
- -------------------------------------------------------------------------------------------------------------------------
     9          18,590    July 1, 2001           December 31, 2011        $446,160.00        $506,577.50          2.83%
- -------------------------------------------------------------------------------------------------------------------------
    10          18,590    July 1, 2001           December 31, 2010        $446,160.00        $506,577.50          2.83%
- -------------------------------------------------------------------------------------------------------------------------
    11          18,590    January 1, 2000        December 31, 2010        $446,160.00        $506,577.50          2.83%
- -------------------------------------------------------------------------------------------------------------------------
    12          18,590    January 1, 2000        December 31, 2010        $446,160.00        $506,577.50          2.83%
- -------------------------------------------------------------------------------------------------------------------------
    13          18,590    January 1, 2001        December 31, 2010        $446,160.00        $506,577.50          2.83%
- -------------------------------------------------------------------------------------------------------------------------
    14          18,590    December 18, 1999      December 31, 2010        $446,160.00        $506,577.50          2.83%
- -------------------------------------------------------------------------------------------------------------------------
    17          18,302    December 18, 2000      December 31, 2010        $466,701.00        $549,060.00          2.79%
- -------------------------------------------------------------------------------------------------------------------------



                                     -iii-
<PAGE>   10

- -------------------------------------------------------------------------------------------------------------------------
                                                                                              

    18          18,369    January 1, 2000        December 31, 2009        $468,409.50        $551,070.00          2.80%
- -------------------------------------------------------------------------------------------------------------------------
    19          18,926    January 1, 2000        December 31, 2009        $482,613.00        $567,780.00          2.88%
- -------------------------------------------------------------------------------------------------------------------------
    20          18,923    January 1, 2000        December 31, 2009        $482,536.50        $567,690.00          2.88%
- -------------------------------------------------------------------------------------------------------------------------
    21          18,923    January 1, 2000        December 31, 2009        $482,536.50        $567,690.00          2.88%
=========================================================================================================================



                                      -iv-

<PAGE>   11
Construction Allowances:



===============================================================================================================
         Floor                      Construction                      Floor                     Construction
                                     Allowance                                                   Allowance
- ---------------------------------------------------------------------------------------------------------------
                                                                                      
        Floor 2                      $40,410.00                     Floor 10                    $650,650.00
       Galleria

        Floor 2                     $711,225.00                     Floor 11                    $557,700.00
       Building

        Floor 3                     $206,220.00                     Floor 12                    $557,700.00

        Floor 4                     $619,580.00                     Floor 13                    $650,650.00

        Floor 5                     $557,700.00                     Floor 14                    $650,650.00

        Floor 6                     $650,650.00                     Floor 17                    $640,570.00

        Floor 7                     $557,700.00                     Floor 18                    $551,070.00

        Floor 8                     $650,650.00                     Floor 19                    $567,780.00

        Floor 9                     $650,650.00                     Floor 20                    $567,690.00

                                                                    Floor 21                    $567,690.00
===============================================================================================================





                                       -v-
<PAGE>   12
Permitted Use:                      Except as to Floor 2 Galleria, general
                                    executive and administrative offices
                                    consistent with Class A office buildings in
                                    the Downtown Financial District and, in
                                    addition, as to Floor 2 Building of the
                                    Premises, photocopying facilities; and as to
                                    Floor 3 of the Premises, mail room, storage,
                                    and photocopying facilities; and as to Floor
                                    2 Galleria, a travel agency providing travel
                                    services, advice and sales at retail to the
                                    public, and/or securities brokerage services
                                    providing services and/or advice to the
                                    public at retail with respect to the
                                    purchase and sale of, or investment in,
                                    securities and other investment vehicles,
                                    and/or the sale of clothing items to the
                                    public at retail bearing Tenant's or
                                    Tenant's Affiliates logos and/or
                                    identifications.

Antenna:                            The rooftop microwave dish or antenna which
                                    may be located in the Antenna Area,
                                    including all replacements thereof effected
                                    by Tenant from time to time.

Antenna Areas:                      Those areas of the roof of the Complex shown
                                    on Exhibit A-20 where the Antenna may be
                                    located.

Antenna Fee:                        The fair market rent for the Antenna Area.

Generator:                          The generator which may be located in the
                                    Generator Area, including all replacements
                                    thereof effected by Tenant from time to
                                    time.

Generator Area:                     The portion of the basement and/or roof of
                                    the Complex where the Generator may be
                                    located.

Building Directory

                                      -vi-
<PAGE>   13
Spaces:                             On the Lease Date, for the Existing
                                    Premises, the number of Building Directory
                                    Spaces utilized by Tenant as of the Lease
                                    Date, and for each Floor in the New
                                    Premises, the number of Building Directory
                                    Spaces allocated to such Floor immediately
                                    prior to the Delivery Date applicable to
                                    such Floor; and after the Delivery Date for
                                    a Floor to Tenant, if additional Building
                                    Directory Spaces become available and Tenant
                                    then desires additional Building Directory
                                    Spaces for the Premises, then the number of
                                    Building Directory Spaces so available and
                                    desired to be used by Tenant up to Tenant's
                                    Proportionate Share of the total Building
                                    Directory Spaces then on the Building
                                    Directory.

Brokers:

Landlord's Broker:                  Cushman & Wakefield of California, Inc.

Tenant's Broker:                    Colliers Damner Pike

Exhibits:

         Exhibit A-1 to A-19:       Floor Plans of Premises
         Exhibit A-20:              Antenna Area
         Exhibit B:                 Landlord's Work for Floors 2 and 3
         Exhibit C:                 Existing Tenant Options
         Exhibit D:                 List of Multi-Tenant Floors
         Exhibit E:                 Categories for Escalation Charges
                                    Statement

         Exhibit F-1, F-2:          Confidentiality Agreements
         Exhibit G:                 List of Recorded Documents
         Exhibit H:                 Janitorial Services
         Exhibit I:                 Rules and Regulations of the
                                    Complex

         Exhibit J:                 Tenant's Signage

                                      -vii-

<PAGE>   14
                                  OFFICE LEASE

         THIS OFFICE LEASE (the "Lease") is made and entered into by and between
Landlord and Tenant as of the Lease Date.

         Landlord and Tenant hereby agree as follows:

         1.  Definitions.

                  1.1.  Terms Defined.  The following terms have the meanings
set forth below.  Certain other terms have the meanings set forth elsewhere in
this Lease.

                           Additional Charges: Escalation Charges and all other
additional charges and amounts payable by Tenant in accordance with this Lease.

                           Additional Security: A written guarantee of each and
every obligation of Tenant under this Lease, in form and substance satisfactory
to Landlord and its counsel in their sole discretion, and containing all
customary waivers of suretyship and other defenses, delivered by an Affiliate of
Tenant in favor of Landlord as of the applicable date, which Affiliate has a
then net worth not less than Four Hundred Seventy-Five Million Dollars
($475,000,000.00), as evidenced by such Affiliate's separate, unconsolidated
audited financial statements with a clean and unqualified opinion delivered to
Landlord by such Affiliate with such guarantee (which audited financial
statements shall have been issued not more than fifteen [15] months prior to the
applicable date).

                           Affiliate: Any subsidiary or parent of a party, any
subsidiary of a parent of a party, any entity in which a party owns a majority
interest, any entity with which a party may merge or consolidate, or any entity
to which a party sells or transfers all


                                      -1-
<PAGE>   15
or substantially all of its assets or transfers all or substantially all of its
stock or other beneficial ownership interests; and as to Tenant, the following
entities: (i) The Charles Schwab Corporation, Schwab (SIS) Holdings, Inc. I,
Schwab (SIS) Holdings, Inc. II, Charles Schwab (Cayman) Limited, Charles Schwab
Holdings (U.K.), Charles Schwab (U.K.), ShareLink Investment Services,
ShareFinder, ShareLink Nominees Limited, ShareLink, ShareLink Services Limited,
Schwab Holdings, Inc., Charles Schwab Limited, Charles Schwab (Hong Kong)
Limited, Mayer and Schweitzer, Inc., Charles Schwab Investment Management, Inc.,
The Charles Schwab Trust Company, Performance Technologies, Inc., TrustMark,
Inc., and Schwab Retirement Services, Inc.; and (ii) such other financial
services entities (including insurance services) in which Tenant or any of the
foregoing entities may subsequently own at least a majority interest.

                          Alterations: Alterations, additions or other
improvements to the Premises made by or on behalf of Tenant.

                          Building: The high-rise office portion of the Complex,
including related Common Areas, commonly known as Telesis Tower, including the
Complex parking garage. The Building does not include the Galleria, other than
the portion of the Complex parking garage which may be located under the
Galleria.

                         Building Holidays: New Year's Day, Presidents' Day,
Memorial Day, Fourth of July, Labor Day, Thanksgiving Day, and Christmas Day,
and such other days designated as holidays under applicable California or
Federal law, or ordinance or resolution of the City and County of San Francisco,
or under contracts with any union governing or covering the Building, if
Landlord is either required to adhere to such laws, ordinance, resolution and/or
contract or determines, in its reasonable


                                      -2-
<PAGE>   16
judgment, based thereon and based on the practices of Comparable Buildings, to
designate such day a Building Holiday.

                          Building Operating Expenses: All reasonable and actual
costs of management, preservation, operation, maintenance and repair of the
Building and supporting facilities serving the Building, including: (i)
salaries, wages, bonuses, retirement plan contributions, other compensation, and
all payroll burden of employees, and all payroll, social security, worker's
compensation, unemployment and similar taxes and impositions with respect to
such employees, and the cost of providing disability or other benefits imposed
by law or otherwise with respect to such employees; (ii) property management
fees and expenses, including a management fee to Landlord to the extent Landlord
shall perform any management of the Building in lieu of a third party manager;
(iii) fair market rent and expenses for the management office for the Complex;
(iv) electricity, natural gas, water, waste disposal, rubbish removal and
recycling, sewer, steam, heating, lighting, air conditioning and ventilating and
other utilities; (v) janitorial, maintenance, security, life safety and other
services, such as alarm service, window cleaning, elevator maintenance,
landscaping, exterminators, and uniforms (and the clean-up or replacement
thereof) for personnel providing services to the Building; (vi) materials,
supplies, tools and rental equipment; (vii) license, permit and inspection fees
and costs; (viii) insurance premiums and costs (including earthquake and/or
flood if carried by Landlord, to the extent permitted in Sections 14.2 and
14.4); (ix) the deductible portion of any insured loss under Landlord's
insurance to the extent permitted in Sections 14.2 and 14.4, except that the
deductible portion of any insured loss for the repair of damage or


                                      -3-
<PAGE>   17
destruction covered by Landlord's insurance shall be amortized on a
straight-line basis over the useful life of improvements made to effect such
repair and reconstruction at an interest rate of 10% per annum, provided that
the total annual amortization amount allocable to Tenant as part of Escalation
Charges shall not exceed a sum equal to the product of $5.00 and the Rentable
Area and Galleria Rentable Area contained in the Premises in each calendar year
during the Term; (x) sales, use and excise taxes; (xi) legal, accounting and
other professional services for the Building, including costs, fees and expenses
of preparing reports, information and analyses for Landlord of the management,
operation, and income and receipts of the Building, and costs, fees and expenses
of contesting the validity or applicability of any law, ordinance, rule,
regulation or order relating to the Building; (xii) the cost of supplies and
services such as telephone, courier services, postage and stationary supplies;
(xiii) normal repair and replacement of worn-out equipment, facilities and
installations; (xiv) depreciation on personal property, including exterior
window draperies provided by Landlord and Common Area floor coverings, and/or
rental costs of leased furniture, fixtures, and equipment; and (xv) expenditures
for capital improvements made at any time to the Building (A) that are intended
in Landlord's judgment as labor saving devices, or to reduce or eliminate other
Building Operating Expenses or to effect other economies in the operation,
maintenance, or management of the Building, or (B) that are necessary or
appropriate in Landlord's judgment for the health and safety of occupants of the
Building, or (C) that are required under any law, ordinance, rule, regulation or
order which was not applicable to the Building at the time it was constructed,
all


                                      -4-
<PAGE>   18
amortized on a straight-line basis over the useful life of the capital
improvements, determined in accordance with GAAP, at an interest rate of 10% per
annum. Building Operating Expenses shall not include: (1) Real Estate Taxes; (2)
Impositions; (3) legal, accounting or other professional fees incurred in
connection with negotiating, preparing or enforcing leases or lease terms,
amendments of leases, terminations of leases or extensions of leases,
proceedings against any tenant (including Tenant) relating to the collection of
rent or other sums due Landlord from such tenant or any other disputes with any
tenant (including Tenant); (4) depreciation, except as expressly set forth in
clause (xiv) above; (5) except as a component of amortization as set forth in
clauses (ix) and (xv) above, interest, including interest on debt, debt service
or amortization payments on any mortgage encumbering the Building (or any
portion thereof) and any financing and refinancing costs with respect thereto;
(6) capital items repairs and replacements, except as set forth in clauses (ix)
and (xv) above; (7) the cost of the design, construction, renovation,
redecorating or other preparation of tenant improvements for Tenant or other
tenants or prospective tenants of the Building (including design fees for space
planning and all third party fees and charges, permit, license and inspection
fees), and moving expenses to move in or out, or relocate, Tenant or other
tenants to or from the Building or within the Building, and allowances for any
of the foregoing; (8) real estate brokerage and leasing commissions and fees;
(9) advertising and promotional expenses incurred for the purpose of leasing
space in the Building or promoting patronage of the Building by invitees; (10)
wages, salaries, reimbursable expenses, benefits and other compensation of any
personnel above

                                      -5-
<PAGE>   19
the grade of the building manager of the Complex; (11) legal costs incurred in
connection with the initial development, construction or improvement of the
Building; (12) any rental under any ground or underlying lease; (13) repairs and
improvements paid for from the proceeds of insurance (or which would have been
paid from the proceeds of insurance required to be carried by Landlord under
this Lease if Landlord has failed to carry such insurance, or which would have
been paid from the proceeds of insurance, but for deductibles under policies
carried by Landlord under Article 14 in excess of those Landlord is permitted to
carry under Article 14), and repairs and improvements paid for directly by
Tenant, any other tenants of the Building, or any third party, and repairs or
improvements made for the benefit solely of individual tenants of the Building
other than Tenant, and deductibles in excess of those Landlord is permitted to
carry under this Lease, and the deductible portion of any insured loss in excess
of those amounts permitted pursuant to clause (ix) above; (14) loss, or the cost
to repair any damage or destruction to the Building, not covered by insurance
carried by Landlord pursuant to this Lease or otherwise carried by Landlord;
(15) any expense for which Landlord is entitled to be reimbursed by any tenant
(including Tenant) as an additional charge in excess of base rent and such
tenant's share of Building Operating Expenses; (16) amounts received by Landlord
through proceeds of insurance to the extent they are compensation for sums
previously included in Building Operating Expenses; (17) Landlord's income taxes
and franchise, gains or estate taxes imposed upon the income of Landlord; (18)
costs with respect to the creation of a mortgage or a superior lease or in
connection with a sale of the Building, including survey, legal fees and


                                      -6-
<PAGE>   20
disbursements, transfer stamps and appraisals, engineering and inspection
reports associated with the contemplated sale; (19) payment of damages,
attorneys' fees and any other amounts to any person seeking recovery for bodily
injury, death or property damage due to Landlord's or its agents' negligence or
other tortious acts committed by Landlord or its agents (including any tort
claims relating to asbestos); (20) the cost of any repairs, alterations,
additions, improvements or replacements made to rectify, remedy or correct any
structural or other defect in the original design, construction materials,
installations or workmanship of the Building; (21) costs incurred due to
violations by Landlord, or by any tenant (including Tenant) in the Building, of
the terms and conditions of any lease, and penalties and interest for late
payment of any obligation of Landlord (unless such penalties or interest result
from Tenant's late payment of Rent and Additional Charges); (22) any tenant
improvement allowance given to any tenant (including Tenant), whether given by
contribution or credit against rent or otherwise, and any abatements or credits
to base rent or additional rent; (23) the costs incurred in performing work or
furnishing services for any tenant (including Tenant) in the Building, whether
at such tenant's or Landlord's expense, to the extent that such work or service
is in excess of any work or service that Landlord is obligated to furnish to
Tenant under this Lease; (24) any rental concessions to, or lease buy-outs of,
Tenant or any other tenant in the Building; (25) the portion of the premium for
earthquake insurance (if carried by Landlord pursuant to Section 14.2)
attributable to coverage under such earthquake insurance for deductibles less
than permitted under Section 14.2 or for coverage exceeding that permitted under


                                      -7-
<PAGE>   21
Section 14.2; (26) costs incurred by Landlord to cure any violation of its
obligations with respect to Hazardous Materials under Section 8.7 below and
costs to comply with the recommendations described in the Phase I Report; (27)
the costs, expenses and fees of any asset manager or investment advisor
representing Landlord or any partner or any other constituent member of
Landlord; (28) rent or rental value for any management office in the Complex in
excess of the amount permitted under clause (iii) above; (29) Landlord's
internal overhead expenses, including the cost of internal accounting and the
cost of preparation of Landlord's income tax or information returns; (30)
overhead and profit increment paid to Affiliates of Landlord for services on or
to the Building (other than any property management fees payable pursuant to
clause (ii) above), or for supplies or other materials, to the extent that such
increment or the cost of such supplies or materials exceed such increment or
costs in Comparable Buildings; (31) the costs for utilities to service the
Complex parking garage, the premiums for insurance covering the Complex parking
garage, and salaries, wages, bonuses, retirement plan contributions or other
compensation, and all payroll burden of employees engaged directly in the
operation of the Complex parking garage, and all payroll, social security,
worker's compensation, unemployment, and similar taxes and impositions with
respect to such employees, and the cost of providing disability or other
benefits imposed by law or otherwise with respect to such employees; (32) any
costs (including compensation paid to clerks, attendants or other persons)
incurred for concessions (such as a newspaper stand or flower stand) or
specialty use (such as a fitness center) operated by Landlord with the intent to
make a profit;


                                      -8-
<PAGE>   22
(33) damages and repairs necessitated by the gross negligence or willful
misconduct of Landlord or Landlord's employees, contractors or agents; (34)
Galleria Operating Expenses; and (35) any costs expressly excluded as a Building
Operating Expenses under any other provisions of this Lease. Building Operating
Expenses shall be "net" so that they are reduced by the amount of all
recoupments, discounts, credits, reductions, allowances or the like actually
received by Landlord from third parties, on account of Building Operating
Expenses, except that Landlord may include in Building Operating Expenses the
reasonable and actual costs and expenses, if any, incurred by Landlord in
obtaining such recoupments, discounts, credits, reductions, allowances or the
like. For purposes of determining Building Operating Expenses, whenever Building
Operating Expenses are derived from costs or expenses attributable to the
Complex, Landlord shall determine the allocation of such costs and expenses to
Building Operating Expenses in accordance with GAAP based on the operating
principles and practices for the Complex, consistently applied, including usage
of the affected portion of the Complex as of the time in question, and the time
or labor devoted to an item or matter as of the time in question. If less than
ninety-five percent (95%) of the entire Rentable Area of the Building is
occupied in any calendar year during the Term (including the Base Year), then
Building Operating Expenses for that year shall be adjusted to reflect
Landlord's reasonable estimate of Building Operating Expenses had 95% of the
entire Rentable Area of the Building been continuously occupied. The
determination of Building Operating Expenses shall be made by Landlord in
accordance with GAAP based on the provisions of this definition of Building
Operating Expenses.


                                      -9-
<PAGE>   23
                           Building Property Taxes:  Eighty-Eight and Four-
Tenths Percent (88.4%) of Real Estate Taxes, except that to the extent the
Building, or a portion thereof, is separately assessed, then One Hundred Percent
(100%) of such separately assessed Real Estate Taxes.

                          Business Days: Monday through Friday of each week,
excluding, however, Building Holidays.

                          Comparable Buildings: The following buildings located
in the Downtown Financial District: One Embarcadero Center; Two Embarcadero
Center; Three Embarcadero Center; Four Embarcadero Center; One Market Plaza; and
101 California Street.

                          Complex: The Land, the Building, the Galleria, all
other buildings, other improvements and building systems at any time located on
the Land, and all appurtenances related thereto, commonly known as Pacific
Telesis Center.

                          Common Areas: Those areas of the Complex designated by
Landlord from time to time for the nonexclusive use of occupants of the Complex,
and their agents, employees, customers, invitees and licensees, and other
members of the public. Except to the extent that the use thereof is granted to
Tenant pursuant to this Lease and then only to the extent of such grant, Common
Areas do not include the exterior windows and walls and the roof of the Complex,
or any space in the Complex (including in the Premises) used for common shafts,
stacks, pipes, conduits, ducts, electrical or other utilities, or other Complex
service facilities, the use of and access to which are reserved exclusively to
Landlord.

                          Critical Area: Facilities and/or equipment located in
a portion of the Premises, the use or operation of, or


                                      -10-
<PAGE>   24
access to which, is reasonably required by Tenant for the conduct by Tenant of
its business in another portion or portions of the Premises.

                          Downtown Financial District: That portion of the City
and County of San Francisco, California, located within the area from the
intersection of Kearny Street and Market Street, along Kearny Street to
Washington Street, along Washington Street to The Embarcadero, along The
Embarcadero to Howard Street, along Howard Street to Spear Street, along Spear
Street to Market Street, and along Market Street to Kearny Street.

                          Environmental Laws: All present and future statutes,
ordinances, orders, rules and regulations of all federal, state or local
governmental agencies relating to the environment, health and safety, or the
use, generation, handling, emission, release, discharge, storage or disposal of
Hazardous Materials.

                          Escalation Charges: As to each Floor of the Premises,
other than Floor 2, Tenant's Percentage Share of the total Dollar increase, if
any, in Building Operating Expenses, and Tenant's Percentage Share of the total
Dollar increase, if any, in Building Property Taxes, each as incurred by
Landlord in each calendar year, or part thereof, after the Base Year applicable
to such Floor, over the amount of Building Operating Expenses and of Building
Property Taxes for the Base Year applicable to each Floor; and as to Floor 2 of
the Premises, Tenant's Percentage Share of Galleria Operating Expenses, and
Tenant's Percentage Share of Galleria Property Taxes, each as incurred by
Landlord in each calendar year, or part thereof, during the Term applicable to
Floor 2.


                                      -11-
<PAGE>   25
                          Executive Floors: A Floor or Floors within the highest
three (3) Floors in the Building then comprised in the Premises which is
occupied mainly by executives of Tenant with the rank of Senior Vice President
and above and their support staff.

                          Existing Premises: Floors 5, 7, 11, 12, 18, 19, 20,
21, and approximately 6,214 feet of Rentable Area on Floor 4 of the Building
occupied by Tenant as of the date hereof.

                          Floor: The entire Rentable Area of any Floor in the
Building, except as to Floor 2 (also designated as "Level 3" of the Galleria) of
the Premises, which is comprised of 15,805 feet of Galleria Rentable Area for
Floor 2 Building, and 1,347 feet of Galleria Rentable Area for Floor 2 Galleria,
as shown on Exhibits A-1 and A-19. References in this Lease to "Floor 2" shall
mean the entirety of Floor 2 included in the Premises, as shown on Exhibits A-1
and A-19; references in this Lease to "Floor 2 Building" shall mean that portion
of Floor 2 shown on Exhibit A-1; and references in this Lease to "Floor 2
Galleria" shall mean that portion of Floor 2 shown on Exhibit A-19.

                          GAAP: Generally accepted accounting principles and
practices.

                          Galleria: The retail shopping center portion of the
Complex, including related Common Areas, and the Galleria roof garden located on
top of the third (3rd) level of the Galleria, commonly known as The Crocker
Galleria, and including the Complex parking garage. The Galleria does not
include the Building, other than the portion of the Complex parking garage which
may be located under the Building.

                          Galleria Operating Expenses: All reasonable and actual
costs of management, preservation, operation,


                                      -12-
<PAGE>   26
maintenance and repair of the Galleria and supporting facilities serving the
Galleria, including: (i) salaries, wages, bonuses, retirement plan
contributions, other compensation, and all payroll burden of employees, and all
payroll, social security, worker's compensation, unemployment and similar taxes
and impositions with respect to such employees, and the cost of providing
disability or other benefits imposed by law or otherwise with respect to such
employees; (ii) property management fees and expenses, including a management
fee to Landlord to the extent Landlord shall perform any management of the
Galleria in lieu of a third party manager; (iii) fair market rent and expenses
for the management office for the Complex; (iv) electricity, natural gas, water,
waste disposal, rubbish removal and recycling, sewer, steam, heating, lighting,
air conditioning and ventilating and other utilities; (v) janitorial,
maintenance, security, life safety and other services, such as alarm service,
window cleaning, elevator maintenance, landscaping, exterminators, and uniforms
(and the clean-up or replacement thereof) for personnel providing services to
the Galleria; (vi) materials, supplies, tools and rental equipment; (vii)
license, permit and inspection fees and costs; (viii) insurance premiums and
costs (including earthquake and/or flood if carried by Landlord, to the extent
permitted in Sections 14.2 and 14.4); (ix) the deductible portion of any insured
loss under Landlord's insurance to the extent permitted in Sections 14.2 and
14.4, except that the deductible portion of any insured loss for the repair of
damage or destruction covered by Landlord's insurance shall be amortized on a
straight-line basis over the useful life of improvements made to effect such
repair and reconstruction at an interest rate of 10% per annum, provided

                                      -13-
<PAGE>   27
that the total annual amortization amount allocable to Tenant as part of
Escalation Charges shall not exceed a sum equal to the product of $5.00 and the
Rentable Area and Galleria Rentable Area contained in the Premises in each
calendar year during the Term; (x) sales, use and excise taxes; (xi) legal,
accounting and other professional services for the Galleria, including costs,
fees and expenses of preparing reports, information and analyses for Landlord of
the management, operation, and income and receipts of the Galleria, and costs,
fees and expenses of contesting the validity or applicability of any law,
ordinance, rule, regulation or order relating to the Galleria; (xii) the cost of
supplies and services such as telephone, courier services, postage and
stationary supplies; (xiii) normal repair and replacement of worn-out equipment,
facilities and installations; (xiv) depreciation on personal property, including
exterior window draperies provided by Landlord and Common Area floor coverings,
and/or rental costs of leased furniture, fixtures, and equipment; (xv)
expenditures for capital improvements made at any time to the Galleria (A) that
are intended in Landlord's judgment as labor saving devices, or to reduce or
eliminate other Galleria Operating Expenses or to effect other economies in the
operation, maintenance, or management of the Galleria, or (B) that are necessary
or appropriate in Landlord's judgment for the health and safety of occupants of
the Galleria, or (C) that are required under any law, ordinance, rule,
regulation or order which was not applicable to the Galleria at the time it was
constructed, all amortized on a straight-line basis over the useful life of the
capital improvements, determined in accordance with GAAP, at an interest rate of
10% per annum; (xvi) advertising and promotional expenses (including fees paid
to third parties) incurred for the


                                      -14-
<PAGE>   28
purpose of marketing and promoting the retail operations of the Galleria; and
(xvii) costs and expenses for the management, preservation operation and
maintenance and repair of the Galleria roof garden located on the third level of
the Galleria, subject to the limitations on such costs and expenses set forth in
this definition of Galleria Operating Expenses. Galleria Operating Expenses
shall not include: (1) Real Estate Taxes; (2) Impositions; (3) legal, accounting
or other professional fees incurred in connection with negotiating, preparing or
enforcing leases or lease terms, amendments of leases, terminations of leases or
extensions of leases, proceedings against any tenant (including Tenant) relating
to the collection of rent or other sums due Landlord from such tenant or any
other disputes with any tenant (including Tenant); (4) depreciation, except as
expressly set forth in clause (xiv) above; (5) except as a component of
amortization as set forth in clauses (ix) and (xv) above, interest, including
interest on debt, debt service or amortization payments on any mortgage
encumbering the Galleria (or any portion thereof) and any financing and
refinancing costs with respect thereto; (6) capital items repairs and
replacements, except as set forth in clauses (ix) and (xv) above; (7) the cost
of the design, construction, renovation, redecorating or other preparation of
tenant improvements for Tenant or other tenants or prospective tenants of the
Galleria (including design fees for space planning and all third party fees and
charges, permit, license and inspection fees), and moving expenses to move in or
out, or relocate, Tenant or other tenants to or from the Galleria or within the
Galleria, and allowances for any of the foregoing; (8) real estate brokerage and
leasing commissions and fees; (9) advertising and promotional expenses incurred
for the purpose


                                      -15-
<PAGE>   29
of leasing space in the Galleria; (10) wages, salaries, reimbursable expenses,
benefits and other compensation of any personnel above the grade of the building
manager of the Complex; (11) legal costs incurred in connection with the initial
development, construction or improvement of the Galleria; (12) any rental under
any ground or underlying lease; (13) repairs or improvements paid for from the
proceeds of insurance (or which would have been paid from the proceeds of
insurance required to be carried by Landlord under this Lease if Landlord has
failed to carry such insurance, or which would have been paid from the proceeds
of insurance, but for deductibles under policies carried by Landlord under
Article 14 in excess of those Landlord is permitted to carry under Article 14),
and repairs and improvements paid for directly by Tenant, any other tenants of
the Galleria, or any third party, and repairs or improvements made for the
benefit solely of individual tenants of the Galleria other than Tenant, and
deductibles in excess of those Landlord is permitted to carry under this Lease;
(14) loss or the cost to repair any damage or destruction to the Galleria, not
covered by insurance carried by Landlord pursuant to this Lease or otherwise
carried by Landlord; (15) any expense for which Landlord is entitled to be
reimbursed by any tenant (including Tenant) as an additional charge in excess of
base rent and such tenant's share of Galleria Operating Expenses; (16) amounts
received by Landlord through proceeds of insurance to the extent they are
compensation for sums previously included in Galleria Operating Expenses; (17)
Landlord's income taxes and franchise, gains or estate taxes imposed upon the
income of Landlord; (18) costs with respect to the creation of a mortgage or a
superior lease or in connection with a sale of the Galleria,


                                      -16-
<PAGE>   30
including survey, legal fees and disbursements, transfer stamps and appraisals,
engineering and inspection reports associated with the contemplated sale; (19)
payment of damages, attorneys' fees and any other amounts to any person seeking
recovery for bodily injury, death or property damage due to Landlord's or its
agents' negligence or other tortious acts committed by Landlord or its agents
(including any tort claims relating to asbestos); (20) the cost of any repairs,
alterations, additions, improvements or replacements made to rectify, remedy or
correct any structural or other defect in the original design, construction
materials, installations or workmanship of the Galleria; (21) costs incurred due
to violations by Landlord, or by any tenant (including Tenant) in the Galleria,
of the terms and conditions of any lease, and penalties and interest for late
payment of any obligation of Landlord (unless such penalties or interest result
from Tenant's late payment of Rent and Additional Charges); (22) any tenant
improvement allowance given to any tenant (including Tenant), whether given by
contribution or credit against rent or otherwise, and any abatements or credits
to base rent or additional rent; (23) the costs incurred in performing work or
furnishing services for any tenant (including Tenant) in the Galleria, whether
at such tenant's or Landlord's expense, to the extent that such work or service
is in excess of any work or service that Landlord is obligated to furnish to
Tenant under this Lease; (24) any rental concessions to, or lease buy-outs of,
Tenant or any other tenant in the Galleria; (25) the portion of the premium for
earthquake insurance (if carried by Landlord pursuant to Section 14.2)
attributable to coverage under such earthquake insurance for deductibles less
than permitted under Section 14.2 or for coverage exceeding that permitted under


                                      -17-
<PAGE>   31
Section 14.2; (26) costs incurred by Landlord to cure any violation of its
obligations with respect to Hazardous Materials under Section 8.7 below and
costs to comply with the recommendations described in the Phase I Report; (27)
the costs, expenses and fees of any asset manager or investment advisor
representing Landlord or any partner or any other constituent member of
Landlord; (28) rent or rental value for any management office in the Complex in
excess of the amount permitted under clause (iii) above; (29) Landlord's
internal overhead expenses, including the cost of internal accounting and the
cost of preparation of Landlord's income tax or information returns; (30)
overhead and profit increment paid to Affiliates of Landlord for services on or
to the Galleria (other than any property management fees payable pursuant to
clause (ii) above), or for supplies or other materials, to the extent that such
increment or the cost of such supplies or materials exceed such increment or
costs in Comparable Buildings; (31) the costs for utilities to service the
Complex parking garage, the premiums for insurance covering the Complex parking
garage, and salaries, wages, bonuses, retirement plan contributions or other
compensation, and all payroll burden of employees engaged directly in the
operation of the Complex parking garage, and all payroll, social security,
worker's compensation, unemployment, and similar taxes and impositions with
respect to such employees, and the cost of providing disability or other
benefits imposed by law or otherwise with respect to such employees; (32) any
costs (including compensation paid to clerks, attendants or other persons)
incurred for concessions (such as a newspaper stand or flower stand) or
specialty use (such as a fitness center) operated by Landlord with the intent to
make a profit;

                                      -18-
<PAGE>   32
(33) damages and repairs necessitated by the gross negligence or willful
misconduct of Landlord or Landlord's employees, contractors or agents; (34)
Building Operating Expenses; and (35) any costs expressly excluded as a Galleria
Operating Expenses under any other provisions of this Lease. Galleria Operating
Expenses shall be "net" so that they are reduced by the amount of all
recoupments, discounts, credits, reductions, allowances or the like actually
received by Landlord from third parties, on account of Galleria Operating
Expenses, except that Landlord may include in Galleria Operating Expenses the
reasonable and actual costs and expenses, if any, incurred by Landlord in
obtaining such recoupments, discounts, credits, reductions, allowances or the
like. For purposes of determining Galleria Operating Expenses, whenever Galleria
Operating Expenses are derived from costs or expenses attributable to the
Complex, Landlord shall determine the allocation of such costs and expenses to
Galleria Operating Expenses in accordance with GAAP based on the operating
principles and practices for the Complex, consistently applied, including usage
of the affected portion of the Complex as of the time in question, and the time
or labor devoted to an item or matter as of the time in question. If less than
ninety-five percent (95%) of the entire Galleria Rentable Area of the Galleria
is occupied in any calendar year during the Term, then Galleria Operating
Expenses for that year shall be adjusted to reflect Landlord's reasonable
estimate of Galleria Operating Expenses had 95% of the entire Galleria Rentable
Area of the Galleria been continuously occupied. The determination of Galleria
Operating Expenses shall be made by Landlord in accordance with GAAP based on
the provisions of this definition of Galleria Operating Expenses.

                                      -19-
<PAGE>   33
                          Galleria Property Taxes: Eleven and Six-Tenths
Percent (11.6%) of Real Estate Taxes, except that to the extent the Galleria, or
a portion thereof, is separately assessed, One Hundred Percent (100%) of such
separately assessed Real Estate Taxes shall be included in Galleria Property
Taxes.

                          Galleria Rentable Area: The aggregate square footage
contained within leasable space of the Galleria computed (i) by measuring from
the exterior Galleria walls fronting on public streets, from the inside surface
of other exterior Galleria walls to the finished surface of the corridor side of
corridor partitions, from the center of demising walls separating adjoining
leased premises and from the outside face of tenant storefronts facing the
interior Common Areas of the Galleria; (ii) without deductions for columns and
projections of the Complex; (iii) including and allocating prorata to Galleria
tenants (including Tenant) as applicable, all areas within exterior Galleria
walls serving more than one (1) leased premises, except for elevator shafts and
elevator machine rooms, public stairs, fire towers and fire tower courts and
main telephone and electric switchboards (other than telephone and electric
switchboards leased by a tenant or comprising a special installation by a
tenant); (iv) allocating all areas, including enclosing walls, serving only one
(1) leased premises (such as stairs, elevators, door recesses, toilets,
auxiliary air conditioning facilities, janitorial closets and telephone and
electric closets) to such leased space; and (v) including, and allocating
prorata to all tenants of the Galleria (including Tenant), any other areas
within the exterior Galleria walls which are not intended for the exclusive use
of any leased premises, but excluding the Complex parking garage.



                                      -20-
<PAGE>   34
                          Hazardous Materials: Petroleum, asbestos,
polychlorinated biphenyls, radioactive materials, radon gas or any chemical,
material or substance now or hereafter defined as or included in the definition
of "hazardous substances", "hazardous wastes", "hazardous materials",
"pollutants", "contaminants", "extremely hazardous waste", "restricted hazardous
waste" or "toxic substances", or words of similar import, under any
Environmental Laws.

                          Impositions: Taxes, assessments, charges, excises and
levies, business taxes, license, permit, inspection and other authorization
fees, transit development fees, assessments or charges for housing funds,
service payments in lieu of taxes and any other fees or charges of any kind at
any time levied, assessed, charged or imposed by any federal, state or local
entity, (i) upon, measured by or reasonably attributable to the cost or value of
Tenant's equipment, furniture, fixtures or other personal property located in
the Premises; (ii) to the extent and when Landlord requires Tenant and other
tenants of the Building to pay the same, upon, measured by or reasonably
attributable to the cost or value of any Alterations that exceed or are
different than the then Building-standard improvements; (iii) upon, or measured
by, any Rent and Additional Charges payable hereunder, including any gross
receipts tax; (iv) upon, with respect to or by reason of the development,
possession, leasing, operation, management, maintenance, alteration, repair, use
or occupancy by Tenant of the Premises, or any portion thereof; or (v) upon this
Lease transaction, or any document by which Tenant creates or transfers any
interest or estate in the Premises. Impositions shall not include Real Estate
Taxes, franchise, transfer, inheritance, estate, or capital stock taxes,


                                      -21-
<PAGE>   35
or income taxes measured by the net income of Landlord, or on any document by
which Landlord creates or transfers any interest or estate in the Complex (other
than a lease or occupancy agreement with Tenant), unless any such taxes are
levied or assessed against Landlord as a substitute for, in whole or in part,
any Imposition.

                          Land: The parcel of land shown as Lots 4, 5, 6, 7, 8,
14, 15 and 16 on that certain Parcel Map, filed February 13, 1981, at Page 6, in
Book 19, of Parcel Maps, of the Official Records of the City and County of San
Francisco, California.

                          Lease Rate: The lower of (i) the Prime Rate in effect
from time to time, plus three percent (3%), or (ii) the highest rate permitted
under applicable usury law.

                          Limited Alterations: Alterations which (i) affect the
structure of any portion of the Complex, (ii) affect the appearance of the
exterior of any portion of the Complex (including ceiling and lighting systems,
and window treatments or coverings, in the Premises), (iii) affect the
appearance of Common Areas on a Floor (other than Floors fully occupied by
Tenant), (iv) adversely affect the proper functioning of, or interfere with, the
Complex roof, walls, elevators, heating, ventilating, air conditioning,
electrical, plumbing, security, life safety or other Complex systems, or the use
and enjoyment by other tenants or occupants of the Complex of their premises, or
exceed Tenant's Percentage Share of the capacity which may then be available in
the Complex, (v) result in the imposition on Landlord of any requirement to make
any alterations or improvements to any portion of the Complex (including
handicap access and life safety requirements), other than in the Premises


                                      -22-
<PAGE>   36
if Tenant performs such alterations or improvements at its cost or expense, or
(vi) increase the cost to clean, maintain or repair the Premises.

                           New Premises:  Floors 2, 3, 6, 8, 9, 10, 13,
14, 17, and approximately 12,376 feet of Rentable Area on Floor 4
of the Building.

                           Phase I Report:  Collectively, the Phase I
Environmental Assessment Report, prepared by Landlord's consultant, H+GCL, Inc.,
dated January 4, 1993; the Asbestos Survey Report, prepared by Landlord's
consultant, Hygienics Environmental Services, Inc., dated July 1994; the
Asbestos Survey Report, prepared by Landlord's consultant, H+GCL, dated January
1993; and an Asbestos Operations and Maintenance Program, prepared by Landlord's
consultant, H+GCL, Inc., dated May 1993.

                           Prime Rate:  The rate charged by Wells Fargo
Bank to its most credit-worthy customers for loans making reference to such
prime rate.

                          Real Estate Taxes: Taxes, assessments and charges now
or hereafter levied or assessed upon, or with respect to, the Complex, or any
personal property of Landlord to the extent used in the operation thereof,
whether or not located therein, or Landlord's interest in the Complex or such
personal property, by any federal, state or local entity, including: (i) all
real property taxes and general and special assessments; (ii) charges, fees or
assessments for transit, public improvements, employment, job training, housing,
day care, open space, art, police, fire or other governmental services or
benefits to the Complex; (iii) service payments in lieu of taxes; (iv) any tax,
fee or excise on the use or occupancy of any part of the Complex; (v) any tax
assessment, charge, levy or fee for


                                      -23-
<PAGE>   37
environmental matters or as a result of the imposition of mitigation measures,
such as parking taxes, employer parking regulations or fees or assessments as a
result of the treatment of the Complex, or any portion thereof or interest
therein, as a source of pollution or stormwater runoff; (vi) any other tax, fee
or excise, however described, that may be levied or assessed as a substitute
for, or as an addition to, in whole or in part, any other Real Estate Taxes; and
(vii) reasonable consultants' and attorneys' fees and expenses incurred in
connection with proceedings to contest, determine or reduce Real Estate Taxes to
the extent Tenant would be required to pay Escalation Charges for Real Estate
Taxes with respect to the year to which such fees and expenses relate. Real
Estate Taxes shall not include: (A) franchise, transfer, inheritance, estate or
capital stock taxes, or income taxes measured by the net income of Landlord,
unless any such taxes are levied or assessed against Landlord as a substitute
for, in whole or in part, any Real Estate Tax; (B) Impositions and all similar
amounts payable by tenants of the Complex under their leases; (C) special
assessments levied against the Complex for the construction of improvements
benefitting solely the Complex in connection with its initial construction, or
in connection with alterations, additions or improvements subsequently made by
Landlord to the Complex (except to the extent that such special assessments are
used to finance expenditures for capital improvements includable under this
Lease as a Building Operating Expense and/or Galleria Operating Expense); and
(D) penalties, fines, interest or charges due for late payment of Real Estate
Taxes by Landlord. If any Real Estate Taxes are payable, or may at the option of
the taxpayer be paid, in installments, such Real Estate Taxes shall, together


                                      -24-
<PAGE>   38
with any interest that would otherwise be payable with such installment, be
deemed to have been paid in installments, amortized over the maximum time period
allowed by applicable law.

                           Rent:  Base Rent and the Antenna Fee.

                           Rentable Area:  The aggregate square footage
on each Building Floor within exterior Building walls, measured from the inside
surface of outer glass and extending the plane thereof into non-glass areas,
excluding elevator shafts and elevator machine rooms, public stairs, fire towers
and fire tower courts, and main telephone and electric switchboards (other than
telephone and electric switchboards leased by a tenant or comprising a special
installation by a tenant), with all air conditioning floors and other areas
containing Building equipment or enclosing common pipes, ducts or shafts,
apportioned to the leased space they serve. To calculate Rentable Area for a
partial Floor tenancy, (i) demising walls separating two (2) leased premises
shall be equally divided between such leased premises, (ii) corridor walls to
the finished corridor side shall be included in the Rentable Area of adjacent
leased space, and (iii) core areas (including the finished enclosing walls
thereof but excluding any part leased to a tenant), corridors (excluding the
enclosing walls thereof), and bathrooms shall be apportioned among each leased
premises on such Floor on the basis of the Rentable Area of each such leased
premises (exclusive of such core and corridor areas) in relation to the total
Rentable Area of all leased premises on such Floor (exclusive of such core and
corridor areas).

                           Rent Commencement Date:  For each Floor
comprised in the Existing Premises, sixty (60) days after the Delivery Date
applicable to that Floor; and for each Floor


                                      -25-
<PAGE>   39
comprised in the New Premises, ninety (90) days after the Delivery Date
applicable to that Floor.

                          Requirements: All laws, ordinances, rules,
regulations, orders and other governmental requirements, the requirements of any
independent board of fire underwriters, and any directive or occupancy
certificate issued pursuant to any law by any public officer or officers
applicable to the Complex.

                           Term:  The term of this Lease, as determined for each
Floor in the Premises pursuant to Section 3.1 below.

                           Wattage Allowance:  For each Floor in the Premises a
connected load of 4.5 watts per foot of Rentable Area contained in such Floor
for convenience power, and 1 kilowatt hour per month per foot of Rentable Area
in such Floor (or Galleria Rentable Area in the case of Floor 2) contained in
such Floor. "Lighting Wattage Allowance" means for each Floor in the Premises a
connected load of 1.5 watts per foot of Rentable Area in such Floor (or Galleria
Rentable Area in the case of Floor 2) contained in such Floor. The Wattage
Allowance does not apply to Building standard heating, ventilation and air
conditioning supplied by Landlord to the Premises under this Lease.

                  1.2. Basic Lease Information. The Basic Lease Information is
incorporated into and made a part of this Lease. Each reference in the Lease to
any Basic Lease Information shall mean the applicable information set forth in
the Basic Lease Information, except that in the event of any conflict between an
item in the Basic Lease Information and this Lease, this Lease shall control.

                  1.3. Effect of Certain Defined Terms. The parties acknowledge
that (i) the Rentable Area and Galleria Rentable Area of the Premises, the
Expansion Premises, the Building and the Galleria have been finally determined
by the parties as part of this Lease for


                                      -26-
<PAGE>   40
all purposes, including the calculation of Tenant's Percentage Share and will
not, except as otherwise provided in this Lease, be changed; and (ii) the
percentage for allocation of Building Property Taxes and Galleria Property Taxes
is conclusive and binding on the parties.

         2.  Lease of Premises.

                          2.1. Premises. Landlord leases to Tenant and Tenant
leases from Landlord the Premises, together with the non-


                                      -27-
<PAGE>   41
exclusive right to use, in common with others, the Common Areas, all subject to
the terms, covenants and conditions set forth in this Lease. Landlord reserves
from the leasehold estate hereunder (i) all exterior walls and windows bounding
the Premises, and (ii) all space located within the Premises in the core or
perimeter of the Building now designated or designed for vertical penetrations,
conduits, electric and all other installations for utilities, telecommunications
systems, and other Building systems serving the Complex, the use thereof and
access thereto, subject to the terms of this Lease, and the right to install,
remove or relocate any of the foregoing for service to any part of the Complex,
including the premises of other tenants of the Building.

                  2.2.  Antenna and Antenna Area.

                           a.  Option to Lease Antenna Area.  On the
terms and conditions contained in this Section 2.2, Landlord hereby grants to
Tenant an option to lease one (1) of the Antenna Areas for the installation,
operation and maintenance of the Antenna for the reception and/or transmission
of Tenant's business communications. Notwithstanding the grant to Tenant of the
option to lease one of the Antenna Areas under this Section 2.2, Landlord shall
have the right, without prior notice or obligation to Tenant, to grant licenses
in or lease to third parties any or all of the Antenna Areas, except that, when
and if Landlord grants licenses in or leases all but the last Antenna Area to
third parties, then, if Landlord intends to grant a license in or enter into a
lease with respect to the last Antenna Area with a third party, Landlord shall,
prior to entering into such license or lease, so notify Tenant, and Tenant shall
have seven (7) Business Days after the receipt of Landlord's notice to


                                      -28-
<PAGE>   42
exercise its option to lease the last Antenna Area in accordance with the terms
and conditions set forth in this Section 2.2.

                           b. Procedure to Exercise Option. Tenant may exercise
its option to lease one (1) of the Antenna Areas under this Section 2.2 at any
time during the Term by giving written notice of such exercise to Landlord,
except that if Landlord has given Tenant notice pursuant to Section 2.2.a above
that it intends to grant a license or enter into a lease for the last Antenna
Area and Tenant fails during the 7-Business Day period specified in Section
2.2.a to exercise the option to lease the last Antenna Area, then Tenant's
option to lease any of the Antenna Areas shall terminate unless any of the
Antenna Areas shall again become available during the Term, in which event
Tenant shall again have the option to lease such Antenna Area on the terms and
conditions of this Section 2.2, except that Landlord shall have no obligation to
notify Tenant of the availability of such Antenna Area, and Tenant, if it
desires, shall be solely responsible for inquiring of Landlord regarding the
availability of such Antenna Area. If Tenant duly exercises the option to lease
one of the Antenna Areas pursuant to this Section 2.2.b, such Antenna Area shall
automatically become part of the Premises on the date Landlord actually delivers
possession of the Antenna Area to Tenant pursuant to Section 2.2.e below, on all
the terms and conditions of this Lease, except that (i) the Antenna Fee shall
equal the fair market rent for the Antenna Area, (ii) Tenant's obligation to pay
the Antenna Fee shall commence thirty (30) days after the date Landlord actually
delivers possession of the Antenna Area to Tenant pursuant to Section 2.2.e
below, (iii) the Antenna Area shall not be included in calculating Tenant's
Percentage Share, and (iv) the lease of


                                      -29-
<PAGE>   43
the Antenna Area shall terminate as of the earlier of (A) the date this Lease
terminates for the entirety of the Premises, or (B) the date the lease of the
Antenna Area terminates pursuant to this Section 2.2.

                           c.  Conditions on Exercise.  Tenant's exercise
of the option to lease an Antenna Area shall not be effective if, as of the date
of exercise, a monetary or other material default by Tenant then exists under
this Lease which Tenant has failed to cure after the giving of any applicable
notice and the expiration of any applicable cure period.

                           d.  Determination of Fair Market Rent.

                                    (i)  Fair Market Rent Defined.  As
used in this Section 2.2, "fair market rent" means the monthly rent charged for
antenna areas comparable to the Antenna Area as to which Tenant has exercised
its option hereunder, for the installation and operation of antennas similar to
the Antenna in the Building and Comparable Buildings, except that if Landlord
has received an offer for the grant of a license or lease for the last Antenna
Area pursuant to which Landlord has given notice of its intention to grant a
license in or lease such Antenna Area under Section 2.2.a above, Landlord shall
deliver to Tenant a true copy of such offer, fair market rent shall be the
amount which the third party has offered to pay to Landlord as a license fee or
rent for such Antenna Area, and such amount shall be conclusively binding on the
parties. Unless fair market rent is determined by such a third party offer, then
the determination of fair market rent shall take into account: (i) the length of
the Term and the length of the terms for such comparable antenna areas; (ii) the
rental structure under the licenses and/or leases for such comparable antenna
areas; (iii) the date the licenses or


                                      -30-
<PAGE>   44
leases for such comparable antenna areas were entered into and the then market
conditions under which the license fee or rental structures under such licenses
or leases were negotiated in comparison with current market conditions, except
that no license or lease entered into more than one (1) year prior to the date
of Tenant's exercise of the option to lease an Antenna Area hereunder shall be
considered; and (iv) any other relevant terms or conditions in the licenses
and/or leases for such comparable antenna areas. Fair market rent shall be
determined for the Antenna Area as of the date the Antenna Area is added to the
Premises hereunder.

                           (ii) Determination of Fair Market Rent. Unless fair
market rent is conclusively determined by a third party offer pursuant to
Section 2.2.d(i) above, then within fifteen (15) days after receipt of Tenant's
notice of exercise of its option to lease an Antenna Area under this Section
2.2, Landlord shall deliver to Tenant Landlord's estimate of fair market rent,
and Landlord and Tenant shall thereupon negotiate in good faith for not more
than fifteen (15) days in an attempt to determine fair market rent for the
Antenna Area. If they are able to agree within such 15-day period, then the fair
market rent shall be the amount so agreed upon. If they are unable to agree on
fair market rent within such 15-day period, then within five (5) days after the
expiration of such 15-day period, the parties shall deliver to each other
concurrently at a mutually agreeable place and time their respective final
written estimates of fair market rent on which Landlord would be willing to
lease the Antenna Area to Tenant, and Tenant would be willing to lease the
Antenna Area from Landlord. If each party's final estimate of the fair market
rent is the same, then fair market rent shall


                                      -31-
<PAGE>   45
equal such estimate. If one party's final estimate of fair market rent is ten
percent (10%), or less, higher than the other party's final estimate, then fair
market rent shall equal the average of the two (2) final estimates. In every
other case, fair market rent, based on the 2 final estimates, shall be
determined by arbitration as provided below in Section 31.16. Should the
determination of fair market rent not be completed or agreed upon prior to the
date upon which Tenant's obligation to pay the Antenna Fee commences, Tenant
shall pay the Antenna Fee equal to Landlord's final estimate of fair market rent
made pursuant hereto. If after determination of fair market rent, the Antenna
Fee is less than the amount previously paid by Tenant for such period, Landlord
shall pay the difference to Tenant within thirty (30) days after the date of
such determination, with interest thereon calculated from the date of each
payment of such Rent by Tenant at the Prime Rate plus 1%; and, if after
determination of fair market rent, the Antenna Fee is more than the amount
previously paid Tenant for such period, Tenant shall pay the difference to
Landlord within thirty (30) days after the date of such determination, with
interest thereon calculated from the date of each payment of such Rent by Tenant
at the Prime Rate plus 1%.

                           e.  Delivery of Antenna Area.  Landlord
shall deliver possession of the Antenna Area to Tenant five (5) days after the
date of Tenant's exercise of the option to lease such Antenna Area hereunder.
Landlord shall deliver the Antenna Area in its "as is" condition, without
obligation to make any alterations or improvements to the Antenna Area. If
Landlord, for any reason due to causes beyond the reasonable control of Landlord
(such as governmental regulations), cannot deliver the


                                      -32-
<PAGE>   46
Antenna Area to Tenant by the delivery date herein specified, this Lease shall
not be void or voidable, and Landlord shall not be in default or liable to
Tenant for any loss or damage resulting therefrom. No such delay in delivery of
the Antenna Area for any reason whatsoever shall operate to extend the Term, but
in such event the lease of the Antenna Area shall commence on the actual date
that Landlord delivers possession of the Antenna Area to Tenant.

                           f. Installation, Operation and Maintenance of
Antenna. Tenant shall install, operate, maintain, repair, replace and/or remove
the Antenna in accordance with the applicable provisions of this Lease,
including provisions for the making of Alterations to the Premises and
compliance with applicable laws, ordinance, rules and regulations. Landlord, at
no cost to Landlord, shall cooperate with Tenant in connection with Tenant's
application for required permits and governmental approvals. In addition to
Landlord's right to review and approve the design and specifications of the
Antenna pursuant to the provisions for making of Alterations to the Premises
under this Lease, Landlord shall have the right to withhold approval of the
design and specifications for the Antenna if Landlord determines, in its sole
discretion, that the Antenna will adversely affect the appearance, structure or
proper function of any portion of the Complex (including visibility of the
Antenna from areas on the ground off-site from the Complex), or interfere with
the operation of other telecommunications equipment on the roof of the Complex,
or in any portion of the Complex. If Landlord withholds its approval, then
Tenant, at its option, may either revise the design and specifications and
resubmit them for Landlord's approval hereunder until Tenant obtains Landlord's


                                      -33-
<PAGE>   47
approval hereunder, or revoke the exercise of its option to lease the Antenna
Area. If Tenant so revokes the exercise of its option to lease the Antenna Area
hereunder, then, as of the date of giving Landlord notice of such revocation,
the Antenna Area shall be deleted from the Premises and Tenant shall thereafter
have no further rights or obligations (except those that shall have accrued on
or prior to the effective date of revocation) with respect to the Antenna Area.
Tenant shall bear all costs and expenses of the installation, operation, and
maintenance of the Antenna. Tenant shall have the right to access the Antenna
Area to install, maintain, repair, replace or remove the Antenna, but only in
accordance with such reasonable rules and procedures as Landlord may from time
to time prescribe. Tenant shall repair any and all damage to the Complex,
including the roof of the Complex, caused by the installation, operation,
testing, maintenance, repair, replacement or removal of the Antenna. The Antenna
may only be located on the Antenna Area. After the initial emplacement of the
Antenna, Tenant shall have the right to replace the Antenna in accordance with
the applicable provisions of this Section 2.2.f for installation of the Antenna,
except that if Tenant makes no material change in the design and specifications
for the Antenna previously approved by Landlord under this Section 2.2.f,
Landlord shall not unreasonably withhold its approval of the replacement Antenna
hereunder, unless such change adversely affects the appearance, structure or
function of any portion of the Complex, or interferes with the operation of
other telecommunications equipment on the roof of the Complex, or in any other
portion of the Complex. Tenant shall have the right to install cables or other
installations for the transmission of Tenant's business communications to and
from


                                      -34-
<PAGE>   48
the Antenna to other portions of the Premises in risers, conduits and shafts in
the Building up to but not exceeding Tenant's Percentage Share of the then
existing capacity of such risers, conduits and shafts, in the Building core on
each Floor of the Premises. Such cables or other installations shall be
installed, operated, tested, maintained, repaired, replaced and/or removed in
accordance with the applicable provisions of this Lease, including provisions
for the making of Alterations to the Premises and compliance with applicable
laws, ordinances, rules and regulations. The installation, operation,
maintenance, repair, replacement and/or removal of such cables or other
installations shall be subject to the rights of other tenants and occupants in
the Complex and such rules and procedures as Landlord may from time to time
reasonably prescribe. The performance of the work to install such cables or
installations shall not adversely affect the use, occupancy or quiet enjoyment
by other tenants or occupants of their premises in the Complex; and such cables
and installations shall not adversely affect the structure of the Complex, or
interfere with the operation of other telecommunications equipment or other
Building systems. Such cables and installations shall be subject to Landlord's
right to require Tenant to remove such cables and installations upon removal of
the Antenna from the Antenna Area under this Section 2.2 or on expiration of the
Term. Tenant shall have the right at any time after installation of the Antenna
to remove the Antenna, but upon such removal, the lease of the Antenna Area
hereunder shall terminate and Tenant shall have no further rights or obligations
(except those that shall have accrued on or prior to the effective date of
termination) with respect to the Antenna Area. In any event, Tenant shall remove
the Antenna from the

                                      -35-
<PAGE>   49
Antenna Area on expiration of the Term or earlier expiration of this Lease.

                           g. Electrical Supply to Antenna. When and if Tenant
installs the Antenna hereunder, Landlord shall install, at its cost and expense,
a submeter to measure the electrical consumption of the Antenna, and Tenant
shall pay the cost of electric current as shown by such meter at Landlord's
actual cost for such electricity. Payments with respect to the electricity
consumed by the Antenna shall be in addition to Tenant's obligation to pay
Tenant's Percentage Share of Building Operating Expenses.

                           h. Disclaimer. Landlord makes no representation or
warranty to Tenant that the Antenna Area is fit for Tenant's intended use, nor
shall Landlord be responsible for any interference with the Antenna from other
telecommunication devices or equipment located on the roof of the Complex, other
areas of the Complex, or adjacent property. Tenant shall install, operate, test,
maintain and repair the Antenna in such a manner so as to minimize interference
with the operations of other telecommunication devices, including other antenna,
located in or on the Complex. Tenant shall cease operation of the Antenna upon
receipt of written notice from Landlord that the Antenna is interfering with
other telecommunication devices located in or on the Building or the Complex,
and Tenant shall not resume operation of its Antenna until Landlord is
satisfied, in its reasonable discretion, that the Antenna can be operated
without interfering with the operations of such other telecommunication devices.
During such period of ceased operations, the Antenna Fee for the Antenna Area
shall abate; and if such period of ceased operations continues for more than
one-


                                      -36-
<PAGE>   50
hundred-eighty (180) days, then Landlord shall have the right to terminate the
lease of the Antenna Area hereunder and the right of Tenant to maintain the
Antenna in the Antenna Area (in which event, Tenant shall promptly remove the
Antenna at Tenant's sole cost and expense). Upon such removal, this Lease shall
terminate with respect to the Antenna Area.

                  2.3. Lease for Generator Area. On the terms and conditions
contained in this Section 2.3, Landlord hereby leases to Tenant the Generator
Area at the location established under this Section 2.3 for the installation,
operation, testing and maintenance of the Generator for the exclusive use by
Tenant to support an uninterrupted power supply (UPS) system. The Generator may
only be located in the Generator Area. Prior to installing the Generator
hereunder, Tenant shall notify Landlord of the Generator Area in which Tenant
shall place the Generator. The Generator Area so designated by Tenant shall be
part of the Premises for all purposes of this Lease, except with respect to
calculating Tenant's Percentage Share.

                           a.  Installation, Operation and Maintenance of
Generator. Tenant shall have the right to pursue and obtain the necessary
permits and approvals from all governmental agencies having jurisdiction under
applicable laws, ordinances, rules, regulations, and codes, for the
installation, operation, testing and maintenance of the Generator in the
basement or roof of the Complex. Such permits and approvals shall specify the
location of the Generator Area and the design and specifications for the
Generator. Landlord, at no cost to Landlord, shall cooperate with Tenant in
connection with Tenant's application for such permits and approvals. Landlord
shall have the right to review and approve, in its sole discretion, the specific
location of the


                                      -37-
<PAGE>   51
Generator Area if on the roof and in Landlord's reasonable discretion if in the
basement, and to review and approve the design and specifications for the
Generator established pursuant to such permits and approvals. Without limiting
the generality of Landlord's review and approval rights with respect to the
location of the Generator Area and the design and specifications for the
Generator, Landlord shall have the right to determine, in its sole discretion,
whether such location or design and/or specifications will adversely affect the
appearance or structure of the Complex, and Landlord shall have the right to
determine, in its reasonable discretion, whether such location or design and/or
specifications will interfere with the operation of any Building systems, or the
use, occupancy or quiet enjoyment of any portion of the Complex by other tenants
or occupants, or otherwise adversely affect the operation, maintenance or
quality of the Complex. If Landlord withholds its approval of either the
Generator Area or the design and specifications for the Generator, then Tenant
may, at its option, either (i) reapply for and obtain the necessary permits and
approvals for the installation, operation and maintenance of the Generator based
on a revised design and/or specifications, and resubmit for Landlord's approval
any new location of the Generator Area and/or revised design and specifications
for the Generator established pursuant to such new permits and approvals, or
(ii) terminate its rights and obligations (except for those which shall have
accrued on or prior to the termination date) under this Section 2.3. If Tenant
so obtains such permits and approvals and Landlord approves, in accordance with
the standards of this Section 2.3.a, the location of the Generator Area and the
design and specifications for the Generator, then Tenant may install,


                                      -38-
<PAGE>   52
operate, test, maintain, repair, replace and/or remove the Generator in
accordance with the applicable provisions of this Lease, including provisions
for the making of Alterations to the Premises and compliance with applicable
laws, ordinances, rules, regulations and codes. Tenant shall bear all costs and
expenses of the installation, operation, testing and maintenance of the
Generator. Landlord, at no cost to Landlord, shall cooperate with Tenant in
connection with Tenant's application for required permits and governmental
approvals. Tenant shall have the right to access the Generator Area to install,
operate, test, maintain, replace or remove the Generator, but only in accordance
with such rules and procedures as Landlord may from time to time reasonably
prescribe, and shall repair any and all damage to the Complex, caused by the
installation, operation, testing, maintenance, repair, replacement or removal of
the Generator. After the initial emplacement of the Generator, Tenant shall have
the right to replace the Generator in accordance with the applicable provisions
of this Section 2.3.a for installation of the Generator, except that if Tenant
makes no material change in the design and specifications for the Generator
previously approved by Landlord under this Section 2.3.a, Landlord shall not
unreasonably withhold its approval of the replacement Generator hereunder,
unless such change adversely affects the appearance, structure or function of
any portion of the Complex, or interferes with the operation of Building
systems, or the use, occupancy or quiet enjoyment of any portion of the Complex
by other tenants or occupants, or otherwise adversely affect the operation,
maintenance or quality of the Complex. Tenant shall have the right to install
cables or other installations for the transmission of power to and from the
Generator to other portions


                                      -39-
<PAGE>   53
of the Premises in risers, conduits and shafts in the Building up to but not
exceeding Tenant's Percentage Share of the existing capacity of such risers,
conduits and shafts in the Building core on each Floor of the Premises. Such
cables or other installations shall be installed, operated, tested, maintained,
repaired, replaced and/or removed in accordance with the applicable provisions
of this Lease, including provisions for the making of Alterations to the
Premises and compliance with applicable laws, ordinances, rules and regulations.
The installation, operation, maintenance, repair, replacement and/or removal of
such cables or other installations shall be subject to the rights of other
tenants and occupants in the Complex and such rules and procedures as Landlord
may from time to time reasonably prescribe. The performance of the work to
install such cables or installations shall not adversely affect the use,
occupancy or quiet enjoyment by other tenants or occupants of their premises in
the Complex; and such cables and installations shall not adversely affect the
structure of the Complex, or interfere with the operation of other Building
systems. Such cables and installations shall be subject to Landlord's right to
require Tenant to remove such cables and installations upon removal of the
Generator from the Generator Area under this Section 2.3 or on expiration of the
Term. Tenant shall have the right at any time after installation of the
Generator to remove the Generator, but upon such removal without replacement for
more than three (3) months, the lease for the Generator Area hereunder shall
terminate and Tenant shall have no further rights or obligations (except those
that shall have accrued on or prior to the effective date of termination) with
respect to the Generator Area. In any event, the lease for the Generator shall
terminate,


                                      -40-
<PAGE>   54
and Tenant shall remove the Generator from the Generator Area, on expiration of
the Term or earlier expiration of this Lease.

                           b.  Disclaimer.  Landlord makes no representation
or warranty to Tenant that the Generator Area is fit for Tenant's intended use,
nor shall Landlord be responsible for any interference with the Generator from
other equipment located in the basement and/or on the roof of the Complex, in
any other area of the Complex.

                  2.4. Expansion of Premises. Landlord hereby grants to Tenant
the option to expand the Premises to include the Rentable Area on one or more of
the Floors comprised in the Expansion Premises upon the terms and conditions set
forth in this Section 2.4.

                           a. Notice and Procedure. Landlord shall notify Tenant
whenever, commencing with the commencement of the Term as to any Floor in the
Premises and during the Term, in Landlord's judgment, a Floor, or portion
thereof (references hereinafter contained to "such Floor" being deemed to
include such portions of such Floor) comprised in the Expansion Premises will be
available for delivery to Tenant ("Landlord's Expansion Notice"). In no event
shall Landlord give a Landlord's Expansion Notice more than one (1) year in
advance of the date such Floor will be so available. Landlord's Expansion Notice
shall set forth the proposed delivery date of such Floor. Tenant shall have
sixty (60) days after the date of Landlord's Expansion Notice to deliver to
Landlord Tenant's unconditional written notice of its election to exercise its
option with respect to the Floor in the Expansion Premises identified in
Landlord's Expansion Notice. The failure of Tenant so to exercise its option
with respect to such Floor in the Expansion Premises shall


                                      -41-
<PAGE>   55
terminate Tenant's option to expand with respect to such Floor in the Expansion
Premises, but Tenant shall continue to have an option to expand the Premises on
such Floor in the Expansion Premises when and if such Floor again becomes
available in Landlord's judgment pursuant to this Section 2.4.a. If Tenant so
requests within ten (10) days after the date of Landlord's Expansion Notice,
Landlord shall provide to Tenant, within ten (10) days after Tenant's request,
Landlord's initial, non-binding estimate of the Base Rent for such Floor. If
Floors 15 and 16 in the Expansion Premises are available, Tenant may exercise
its option to expand with respect to both Floors or the 16th Floor only; and if
more than one of Floors 22 - 25 in the Expansion Premises are available, Tenant
may exercise its option to expand with respect to all such Floors or, if Tenant
exercises its option with respect to less than all such Floors, starting with
the lowest of such Floor or Floors in such portions of the Expansion Premises;
and if Floors in the Expansion Premises are available in both Floors 15-16 and
22-25, Tenant may exercise its option to expand with respect to all such Floors
or, if Tenant exercises its option with respect to less than all of such Floors,
Tenant shall exercise its option starting with Floor 16 (if available), then
Floor 15 (if available), and then the lowest of Floors 22-25 then available. The
effectiveness of Tenant's exercise of its option to expand as set forth in this
Section 2.4 is in each instance conditioned on the following as of the date of
delivery of Tenant's notice of its election to exercise such option: (i) Tenant
has not entered into an assignment of this Lease requiring Landlord's consent,
and Tenant (including Tenant's Affiliates) physically occupy at least sixty
percent (60%) of the Premises; (ii) no monetary or other material default


                                      -42-
<PAGE>   56
by Tenant remains uncured after the giving of any applicable notice and the
expiration of any applicable cure period; and (iii) Tenant's net worth is not
less than Four Hundred Seventy-Five Million Dollars ($475,000,000.00), as
evidenced by Tenant's separate, unconsolidated audited financial statements,
with a clean and unqualified auditor's opinion, delivered to Landlord within
twenty (20) days after Landlord's request at any time after Tenant's notice of
exercise of Tenant's option to expand hereunder (which audited financial
statements shall have been issued not more than fifteen [15] months prior to the
applicable exercise date), except that if Tenant does not meet the conditions
specified in this clause (iii), Tenant may provide to Landlord Additional
Security in order to satisfy the conditions specified in this clause (iii).

                           b. Addition of Expansion Premises to Premises. The
Floor in the Expansion Premises as to which Tenant has duly exercised its option
to expand hereunder shall automatically become part of the Premises as of the
actual date of delivery of possession of such Floor to Tenant pursuant to this
Section 2.4, and on all the terms and conditions of this Lease, except that (i)
the Base Rent for such Floor shall be the higher of (A) fair market rent
determined in accordance with Section 2.4.c below, or (B) the Base Rent and
Escalation Charges for the 18th Floor then in effect (or, if the Delivery Date
for the 18th Floor has not yet occurred, the Base Rent and Escalation Charges
for the 18th Floor which would be in effect if the 18th Floor Delivery Date had
occurred, or which would have been in effect but for termination of this Lease
as to the 18th Floor pursuant to Section 2.6 below, if applicable), increased
thereafter by any increase in Base Rent for the 18th Floor as set forth in the

                                      -43-
<PAGE>   57
Basic Lease Information (or which would have been in effect but for termination
of this Lease as to the 18th Floor pursuant to Section 2.6 below, if
applicable), with the same Base Year specified in the Basic Lease Information,
(ii) the Rent Commencement Date for such Floor shall be the date that is ninety
(90) days after the actual delivery of the Floor by Landlord to Tenant
hereunder, (iii) (A) if Tenant has exercised its right to expand the Premises on
a Floor in the Expansion Premises during the initial Term, then Landlord shall
provide to Tenant, in the same manner and subject to the terms and conditions of
Section 10.4 below, a Construction Allowance equal to the product obtained by
multiplying $0.292 (29.2(cent)) times the number of feet of Rentable Area
contained in such Floor times the number of months in the Term applicable to
such Floor (not exceeding, however, the amount of $35.00 times the number of
feet of Rentable Area contained in such Floor), and (B) if Tenant has exercised
its right to expand the Premises on any such Floor during an Extended Term, then
Landlord may, at its sole option, provide to Tenant a Construction Allowance as
a component of fair market rent determined in accordance with clause (iv) of
Section 2.4.c(i) below, and (iv) the Expiration Date for Floors 15 and 16 shall
be coterminous with the Expiration Date for Floors 10, 11, 12, 13, 14 and 17 of
the Premises, and the Expiration Date for Floors 22, 23, 24 and 25 shall be
coterminous with the Expiration Date for Floors 18, 19, 20 and 21 of the
Premises (or which would have been the Expiration Date but for termination of
this Lease as to any such Floor pursuant to Section 2.6 below, if applicable).
Upon the addition of a Floor in the Expansion Premises to the Premises
hereunder, Tenant's Percentage Share for such Expansion Premises shall be that
set forth in the Basic Lease Information


                                      -44-
<PAGE>   58
for such Floor, prorated for partial Floors if applicable. Landlord shall
deliver the Expansion Premises to Tenant in their "as-is" condition, without
obligation to make any alterations or improvements to the Expansion Premises. If
Landlord for any reason whatsoever cannot deliver a Floor in the Expansion
Premises to Tenant by the proposed delivery date set forth in Landlord's
Expansion Notice, this Lease shall not be void or voidable and Landlord shall
not be in default or liable to Tenant for any loss or damage resulting
therefrom, except that (1) if the delay in delivery of such Floor is due to a
holdover occupancy in such Floor by a tenant or subtenant, Landlord shall
promptly undertake commercially reasonable efforts (including commencement of an
unlawful detainer proceeding or proceedings) in order to evict such holdover
occupant and deliver such Floor to Tenant hereunder; and (2) if the delay in
delivery of such Floor extends more than sixty (60) days beyond the proposed
delivery date set forth in Landlord's Expansion Notice, then for a period of
thirty (30) days after the expiration of such 60-day period, Tenant shall have
the right to terminate the exercise of its option to expand the Premises on such
Floor by giving written notice of such termination to Landlord within such
30-day period, but if Tenant fails to give such notice within such 30-day
period, then Tenant shall have no further right to terminate the exercise of its
option to expand the Premises with respect to such Floor and shall accept
delivery of such Floor when and if Landlord delivers such Floor to Tenant. No
delay in delivery of a Floor in the Expansion Premises for any reason whatsoever
shall operate to extend the Expiration Date or the Term. Landlord and Tenant
shall enter into any amendments to this Lease reasonably required by either
Landlord or Tenant to confirm that a Floor in


                                      -45-
<PAGE>   59
the Expansion Premises has been added to the Premises, increasing Tenant's
Percentage Share, confirming the Base Rent, the Base Year, and the Rent
Commencement Date and Expiration Date applicable to such Floor, and such other
amendments as are reasonably required to implement the addition of the Expansion
Premises to the Premises.

                           c.  Determination of Fair Market Rent.

                                    (i) Fair Market Rent Defined. As used in
this Section 2.4, "fair market rent" means the annual base rent charged for full
floor space comparable to the Expansion Premises in Comparable Buildings taking
into account: (i) the length of the Term and the lease terms for such comparable
space; (ii) the rental structure under this Lease and the leases for such
comparable space, including any additional rental and all other payments and
escalations payable under this Lease and under leases of such comparable space,
and the Base Year under this Lease and the base year for such payments under
leases for such comparable space; (iii) the size, location and the Floor level
of the Expansion Premises compared with such comparable space and the views from
the Expansion Premises compared with the views from such comparable space; (iv)
tenant improvement allowances and other monetary concessions made to tenants for
such comparable space and the amount of any Construction Allowance made
available by Landlord pursuant to clause (iii) of Section 2.4.b above; (v) the
date the leases for such comparable space were entered into and the then market
conditions under which the rental structures under such leases were negotiated
in comparison with current market conditions, except that no lease entered into
more than one (1) year prior to the determination date for fair market rent
shall be considered;


                                      -46-
<PAGE>   60
(vi) the quality of the ownership of the Building and Comparable Buildings;
(vii) the quality and financial strength of Tenant as compared with the quality
and financial strength of tenants under such leases; and (viii) any other
relevant terms or conditions in the leases for such comparable space. For
purposes of determining fair market rent, no lease of space in a Comparable
Building shall be utilized if such space contains material quantities of
asbestos, such as asbestos fireproofing or in-slab asbestos. Fair market rent
shall be determined for each Floor in the Expansion Premises as of the date such
Floor is added to the Premises hereunder.

                                    (ii)  Determination of Fair Market Rent.
If Landlord believes that fair market rent is higher than the Base Rent
determined pursuant to clause (i)(B) of Section 2.4.b above, then, within thirty
(30) days after receipt of Tenant's notice of exercise of its right to expand
under this Section 2.4, Landlord shall deliver to Tenant Landlord's estimate of
fair market rent. Landlord and Tenant shall thereupon negotiate in good faith
for not more than thirty (30) days in an attempt to determine fair market rent
for the Floor in the Expansion Premises as to which Tenant has exercised its
expansion option. If they are able to agree within such 30-day period, then the
fair market rent shall be the amount so agreed upon. If they are unable to agree
on fair market rent within such 30-day period, then within ten (10) days after
the expiration of such 30-day period, the parties shall deliver to each other
concurrently at a mutually agreeable place and time their respective final
written estimates of fair market rent on which Landlord would be willing to
lease to Tenant the Floor in the Expansion Premises as to which Tenant has
exercised its expansion option, and Tenant would


                                      -47-
<PAGE>   61
be willing to lease such Floor from Landlord. If each party's final estimate of
the fair market rent is the same, then fair market rent shall equal such
estimate. If one party's final estimate of fair market rent is ten percent
(10%), or less, higher than the other party's final estimate, then fair market
rent shall equal the average of the two (2) final estimates. In every other
case, the fair market rent, based on the 2 final estimates, shall be determined
by arbitration as provided in Section 31.16 below, but in no event shall Base
Rent for any Floor in the Expansion Premises be less than the Base Rent
determined pursuant to clause (i)(B) of Section 2.4.b above, and the arbitrators
conducting the arbitration under Section 31.16 shall be so instructed. Should
the determination of fair market rent not be completed or agreed upon prior to
the date upon which Tenant's obligation to pay Base Rent commences for the Floor
in the Expansion Premises as to which Tenant has exercised its expansion option,
Tenant shall pay annual Base Rent equal to Landlord's final estimate of fair
market rent made pursuant hereto. If after determination of fair market rent,
the annual Base Rent is less than the amount previously paid by Tenant for such
period, Landlord shall pay the difference to Tenant within thirty (30) days
after the date of such determination, with interest thereon calculated from the
date of each payment of such Rent by Tenant at the Prime Rate plus 1%; and, if
after determination of fair market rent, the annual Base Rent is more than the
amount previously paid Tenant for such period, Tenant shall pay the difference
to Landlord within thirty (30) days after the date of such determination, with
interest thereon calculated from the date of each payment of such Rent by Tenant
at the Prime Rate plus 1%.

                                      -48-
<PAGE>   62

                           d.  Substitution of Termination Floors For Certain
Expansion Premises. If Tenant exercises its right to terminate this Lease with
respect to one or more Termination Floors pursuant to Section 2.6 below, then
such Termination Floors as to which such termination right has been exercised
shall be substituted for Floors 22 - 25 of the Expansion Premises in descending
order commencing with Floor 25, unless one of such Floors in the Expansion
Premises for which a Termination Floor has been substituted becomes available
pursuant to this Section 2.4 earlier than such Termination Floor.

                           e. Provisions Applicable to Expansion on Partial
Expansion Premises Floor. Notwithstanding anything to the contrary contained in
this Section 2.4, the provisions of this Section 2.4.e shall govern Tenant's
rights with respect to the exercise of its option to expand with respect to a
portion of a Floor in the Expansion Premises. If Tenant has exercised its option
to expand hereunder with respect to a portion of a Floor in the Expansion
Premises, then Tenant shall have the absolute obligation to accept delivery and
add to the Premises the balance of such Floor when and if the same becomes
available, and such balance of such Floor shall automatically become part of the
Premises as of the actual date of delivery of possession of such balance of such
Floor to Tenant pursuant to this Section 2.4.e, subject, however, to clauses (i)
- - (iv) of Section 2.4.b above, if Landlord can deliver the balance of such Floor
with at least three (3) years remaining in the Term applicable to such Floor.
Landlord shall give Tenant at least one hundred twenty (120) days prior written
notice of delivery of the balance of such Floor in accordance with the
foregoing. If for any reason Landlord cannot deliver the balance of such Floor
with at least three (3) years


                                      -49-
<PAGE>   63
remaining in the Term applicable to such Floor, then such balance of such Floor
shall automatically be deleted from the Expansion Premises, and Tenant shall
have no further rights to expand the Premises to include such balance of such
Floor in the Premises under this Section 2.4.

                  2.5. Notice Right with Respect to Certain Floors. When and if
from time to time during the Term, the entire Rentable Area on any Floor in the
Building from the 26th Floor to the top Floor in the Building (the "High-Rise
Floors") becomes available for Lease, Landlord shall use good faith efforts so
to notify Tenant. Landlord shall have no liability to Tenant for any failure
from any cause whatsoever so to notify Tenant; and no other obligation than the
giving of notice hereunder and such notice shall not give rise to any rights in
Tenant or any duties or obligations of Landlord, such notice being solely for
informational purposes to Tenant. In addition to giving notice hereunder,
Landlord shall respond to inquiries from Tenant made by Tenant from time to time
regarding the availability for lease of High Rise Floors, but Landlord's
response to such inquiries shall not give rise to any rights in Tenant or any
duties or obligations of Landlord, such response being solely for informational
purposes to Tenant.

                  2.6. Limited Right of Termination with Respect to Certain
Floors. On the terms and conditions set forth in this Section 2.6, Landlord
grants to Tenant a one-time right to terminate this Lease as to three (3) Floors
then comprised in the Premises as determined pursuant to this Section 2.6 (the
"Termination Floors").

                           a.  Exercise of Termination Rights.  Tenant
shall have the right to exercise its termination right for one,


                                      -50-
<PAGE>   64
two or all of the Termination Floors. In no event shall Tenant have any
termination right with respect to only a portion of any Termination Floor.
Tenant shall exercise its termination right hereunder, if at all, not earlier
than January 1, 2003, and not later than December 31, 2003. If Tenant exercises
its right to terminate this Lease with respect to one or more of the Termination
Floors, termination shall, subject to the conditions specified in Section 2.6.c
below, be effective twelve (12) months after the date Tenant exercises its
termination right hereunder (the "Termination Date"), and as of the Termination
Date, the Termination Floors as to which Tenant has exercised its termination
right hereunder shall automatically be deleted from the Premises, and all
rights, duties and obligations of the parties with respect to such Termination
Floors shall terminate and be of no further force or effect except for those
obligations which shall have accrued prior to the Termination Date. Landlord
shall promptly refund to Tenant any Rent paid by Tenant for any period after the
Termination Date, and shall promptly refund any Additional Charges after the
exact amount of such Additional Charges has been determined.

                           b.  Limited Right to Substitute Floors.
Except as hereinafter provided for Executive Floors, Tenant shall exercise its
right to terminate this Lease as to the highest three (3) Floors in the Building
then comprised in the Premises. If, however, any one of such 3 Floors is an
Executive Floor, then Tenant shall have the right to except from such 3 Floors
up to two (2) such Executive Floors, and substitute the next Floor or Floors
immediately beneath the Executive Floor or Floors then comprised in the Premises
in lieu thereof.



                                      -51-
<PAGE>   65
                           c.  Termination Consideration.  As consideration for
and a condition of Tenant's right to terminate this Lease with respect to one or
more of the Termination Floors, Tenant shall pay to Landlord an amount equal to
the sum of six (6) months installments of Base Rent for the Termination Floors,
plus the unamortized amount of the Construction Allowances for the Termination
Floors, plus the unamortized amount of all brokers' commissions paid by Landlord
with respect to the Termination Floors. Amortization hereunder shall be straight
line, based on the then remaining initial Term of this Lease, using the
Expiration Date when the Lease would otherwise terminate for each Termination
Floor; and the interest factor for such amortization shall be ten percent (10%)
per annum. Upon receipt by Landlord of Tenant's notice of exercise of its
termination right for one or more Termination Floors hereunder, Landlord shall
calculate the consideration due hereunder, and shall submit such calculation,
together with appropriate backup material, to Tenant. Tenant shall pay the
amount of the consideration as so calculated by Landlord due on account of the
exercise by Tenant of its termination right hereunder within thirty (30) days
after receipt of Landlord's calculation, and Tenant's failure to pay such amount
within such thirty (30) day period shall, at Landlord's written election, given
within thirty (30) days after the expiration of such 30-day period, render the
termination of this Lease as to the Termination Floors null and the Lease shall
remain in full force and effect with respect to the Termination Floors; and if
Tenant disputes the amount of such consideration, Tenant shall notify Landlord
on or before the due date for payment of such consideration, and if the parties
cannot resolve the dispute before such due date, Tenant shall pay the


                                      -52-
<PAGE>   66
consideration as determined by Landlord without prejudice to Tenant's position,
and the dispute shall be resolved by arbitration in accordance with Section
31.17 below.

                           d.  Construction Allowances.  Tenant's exercise of
its right to terminate this Lease with respect to one or more of the Termination
Floors under this Section 2.6 shall terminate Tenant's right to receive payment
of any undisbursed Construction Allowances for such Termination Floors as to
which Tenant has so exercised its right, but shall not affect Tenant's right to
receive payment of any other remaining undisbursed Construction Allowances (or
credit the same against Rent and Additional Charges) pursuant to Section 10.4
below for other Floors then comprised in the Premises, subject, however, to the
terms and conditions specified in Section 10.4 with respect to the disbursement
and/or credit of such Construction Allowances thereunder.

                  2.7. Right of Termination with Respect to Floor 2 Galleria. On
the terms and conditions set forth in this Section 2.7, Landlord grants to
Tenant a one-time right to terminate this Lease as to Floor 2 Galleria. Tenant
may exercise its termination right hereunder by giving written notice of
termination to Landlord not earlier than thirty-six (36) months after the
Delivery Date for Floor 2 Galleria or later than forty-eight (48) months after
such Delivery Date. Termination of this Lease with respect to Floor 2 Galleria
shall be effective on the last day of the fifth (5th) year of the Term
applicable to Floor 2 Galleria. If Tenant exercises its right to terminate this
Lease with respect to Floor 2 Galleria hereunder, then, as consideration for,
and as a condition of, Tenant's right to terminate this Lease with respect to
Floor 2 Galleria, Tenant


                                      -53-
<PAGE>   67
shall pay to Landlord an amount equal to the unamortized amount of the
Construction Allowance for Floor 2 Galleria, plus the unamortized amount of all
broker's commissions paid by Landlord with respect to Floor 2 Galleria.
Amortization hereunder shall be straight line, based on the then remaining
initial Term applicable to Floor 2 Galleria, using the Expiration Date when the
Lease would otherwise terminate for Floor 2 Galleria; and the interest factor
for such amortization shall be ten percent (10%) per annum. Upon receipt by
Landlord of Tenant's notice of exercise of its termination right for Floor 2
Galleria hereunder, Landlord shall calculate any consideration due hereunder,
and shall submit such calculation, together with appropriate backup material to
Tenant. Tenant shall pay the amount of the consideration as so calculated by
Landlord due on account of the exercise by Tenant of its termination right
hereunder within thirty (30) days after receipt of Landlord's calculation; and
if Tenant disputes the amount of such consideration, Tenant shall notify
Landlord on or before the due date for payment of such consideration, and if the
parties cannot resolve the dispute before such due date, Tenant shall pay the
consideration as determined by Landlord without prejudice to Tenant's position,
and the dispute shall be resolved by arbitration in accordance with Section
31.17 below. On or before termination of this Lease with respect to Floor 2
Galleria hereunder, Tenant shall effect such Alterations as are necessary in
order to close any doors or other points of access between Floor 2 Galleria and
Floor 2 Building.

         3.  Term.

                  3.1.  Condition and Acceptance of Premises.



                                      -54-
<PAGE>   68
                           a.  Delivery of Premises; Term.  Except as
hereinafter provided, and unless sooner terminated pursuant to the provisions of
this Lease, the "Term" of this Lease shall commence as to each Floor comprised
in the Premises on the Delivery Date applicable to such Floor set forth in the
Basic Lease Information and end as to such Floor on the applicable Expiration
Date set forth in the Basic Lease Information. Landlord shall deliver possession
of each Floor in the Premises to Tenant on each applicable Delivery Date, vacant
and free of any occupancies, without obligation to make any alterations or
improvements to such Floor, except that (i) Landlord shall before the Delivery
Date for Floor 2, and the Delivery Date for Floor 3, respectively, perform the
Landlord's Work in accordance with Exhibit B; (ii) other than Floors in the
Existing Premises and Floors in the New Premises occupied by Tenant on the date
immediately prior to the Delivery Date for such Floors pursuant to a sublease or
assignment of an existing lease for such Floors, each such Floor shall be
delivered to Tenant in its "as-is" condition as of the Lease Date, except for
(A) ordinary wear and tear occurring between the Lease Date and the Delivery
Date for such Floor, (B) alterations and additions made to such Floor after the
Lease Date but before the Delivery Date by existing tenants and subtenants
occupying such Floors pursuant to the leases of such tenants for such Floor,
except to the extent such alterations or additions exceed or are different than
then customary building standard installations in Class A office buildings
within the Downtown Financial District, and (C) damage or destruction to such
Floor occurring prior to the Delivery Date; and (iii) as to Floors in the
Existing Premises and Floors in the New Premises occupied by Tenant on the date
immediately


                                      -55-
<PAGE>   69
prior to the Delivery Date for such Floors pursuant to a sublease or assignment
of an existing lease for such Floor, each such Floor shall be delivered to
Tenant in its "as-is" condition as of the Delivery Date, except for damage or
destruction to such Floor occurring prior to the Delivery Date. If a tenant or
subtenant of a Floor covered by clause (ii) has, after the Lease Date but before
the Delivery Date for such Floor, made alterations or additions exceeding or
different than the then customary building standard installations in Class A
office buildings within the Downtown Financial District, as specified in clause
(B) of clause (ii) above, Landlord shall so notify Tenant and Tenant shall have
the option exercised by written notice to Landlord given within 20 days after
receipt of Landlord's notice, to have Landlord remove (or cause removal of) such
alterations and additions that exceed or are different than then customary
building standard installations in Class A office buildings within the Downtown
Financial District, or accept delivery of the Floor with such alterations and
additions. If an event of damage or destruction occurs under clause (C) of
clause (ii) above, or under clause (iii) above, Landlord shall so notify Tenant
and, subject to any obligations which Landlord may have to repair or restore
such Floor pursuant to the lease or leases of existing tenants of such Floor (in
which event the provisions of clause (ii) above shall again apply), and except
for any obligation of Tenant to repair alterations on such Floor pursuant to the
lease or other occupancy agreement by which Tenant occupies such Floor, Tenant
shall have the option, exercisable by written notice to Landlord given within 30
days after the event of damage or destruction, to require Landlord to repair and
restore such Floor to its condition existing immediately prior to the date of
the event of

                                      -56-
<PAGE>   70
damage or destruction and deliver such Floor to Tenant in such repaired and
restored condition, or require delivery of such Floor by Landlord in shell
condition before the installation by Tenant of its Alterations on such Floor
pursuant to Section 10.4. Nothing in clause (ii) or (iii) above shall affect or
limit Tenant's right to utilize the Construction Allowances for initial
Alterations to Floors pursuant to Section 10.4. If Landlord can deliver
possession of Floors 2, 3, 8, 9 and/or 10 in the Premises to Tenant before the
applicable Delivery Date, and Landlord elects so to deliver any or all of such
Floors, then Landlord shall so notify Tenant and Tenant shall accept delivery of
such Floor on the date of delivery thereof by Landlord, which date shall be no
sooner than ninety (90) days after the date of Landlord's notice, and such date
of delivery shall constitute the Delivery Date for such Floor. If Landlord can
deliver possession of up to two (2) Floors in the Premises (in addition to
Floors 2, 3, 8, 9 and 10) to Tenant before the applicable Delivery Date, and
Landlord elects so to deliver such Floor or Floors, then Landlord shall so
notify Tenant and Tenant shall accept delivery of such Floor or Floors on the
date which is twelve (12) months after the date of Landlord's notice, and such
date of delivery shall constitute the Delivery Date for such Floor. If Landlord
can deliver possession of a Floor in the Premises to Tenant before the
applicable Delivery Date, other than Floors 2, 3, 8, 9 and 10, and the foregoing
two (2) additional Floors, and Landlord desires to deliver such Floor or Floors
to Tenant, then Landlord shall so notify Tenant and Tenant may accept delivery
of such Floor on the date of delivery specified by Landlord in its notice to
Tenant, and such date of delivery shall constitute the Delivery Date for such
Floor. If Landlord, for any reason


                                      -57-
<PAGE>   71
whatsoever, cannot deliver possession of a Floor in the Premises to Tenant by
the applicable Delivery Date, this Lease shall not be void or voidable, and
Landlord shall not be in default or liable to Tenant for any loss or damage
resulting therefrom, except that (1) if the delay in delivery of such Floor is
due to a holdover occupancy in such Floor by a tenant or subtenant, Landlord
shall promptly undertake commercially reasonable efforts (including commencement
of an unlawful detainer proceeding or proceedings) in order to evict such
holdover occupant and deliver such Floor to Tenant hereunder; and (2) if the
delay in delivery of such Floor extends more than one hundred twenty (120) days
beyond the Delivery Date, then for a period of thirty (30) days after the
expiration of such 120-day period, Tenant shall have the right to terminate this
Lease as to such Floor by giving written notice of such termination to Landlord
within such 30-day period, but if Tenant fails to give such notice within such
30-day period, then Tenant shall have no further right to terminate this Lease
as to such Floor and shall accept delivery of such Floor when and if Landlord
delivers such Floor to Tenant. In the event of a delay in delivery of possession
of a Floor in the Premises hereunder beyond the Delivery Date specified in the
Basic Lease Information, the Delivery Date for such Floor shall be the actual
date that Landlord delivers possession of the Floor to Tenant. No delay in
delivery of the Premises for any reason whatsoever shall operate to extend any
Expiration Date or the Term applicable to a Floor in the Premises. In connection
with the foregoing, (I) Tenant acknowledges that the tenants of the Building
identified in Exhibit C hereto have rights as set forth in Exhibit C to extend
the terms of their leases by which they currently occupy Floors 2, 3, 8, 9, 10,
13 and 17 comprised in


                                      -58-
<PAGE>   72
the New Premises and if any such options to extend are exercised by any such
tenants, then Landlord shall be delayed in delivering such Floor beyond the
applicable Delivery Date for such Floor, and (II) Landlord warrants and
represents to Tenant that Exhibit C sets forth all rights of other tenants of
the Building to extend the terms of their leases with respect to the New
Premises. Upon request of Tenant, Landlord shall use commercially reasonable
efforts to ascertain from any such tenant its intentions with respect to whether
it will exercise its right to extend its term, but subject only to such efforts,
Landlord shall have no obligation of any kind or character to attempt to prevent
such tenant from exercising such option or terminate such option to extend.
Except for an amendment to the lease of any such tenant to delete its right to
extend its term or shorten the term, Landlord shall not agree with any such
tenant to any modification with respect to such tenant's right to extend its
term which would enlarge or extend such tenant's rights beyond those currently
possessed by such tenant as set forth in Exhibit C hereto.

                           b.  Delivery of Partial Floor.  If Landlord
is able to deliver part of a Floor comprising the Premises (but not the entire
Floor) as of the Delivery Date under the Basic Lease Information, then Landlord
shall notify Tenant. Tenant shall have the right, within thirty (30) days after
receipt of Landlord's notice, to elect to take such portion of such Floor as is
available for delivery and thereafter, if Tenant shall have elected to take
delivery of such portion, Landlord shall deliver, and Tenant shall accept
delivery of, the remaining portions of the Floor to Tenant as the same become
available for delivery of possession to Tenant. If Tenant elects to accept
partial


                                      -59-
<PAGE>   73
delivery of a Floor hereunder, then Tenant shall have the right to utilize the
Construction Allowance, pursuant to the terms and conditions of Section 10.4, to
make initial Alterations to such portion of the Floor (including such
Alterations as may be necessary to create a multi-tenant Floor). In connection
with the provisions of this Section 3.1.b, Landlord has identified all Floors
comprised in the Premises which have multiple tenants, all of which are listed
on Exhibit D with the expiration dates of the leases of such tenants and whether
such tenants have any rights of extension of the term of their leases.

                           c.  Scope of Premises and Tenant's Percentage
Share; Proration of Base Rent for Partial Floors. For all purposes under this
Lease, (i) references to the "Premises" shall mean only those Floors (including
Expansion Premises), or portions of Floors, delivered by Landlord to Tenant
pursuant to this Section 3.1 (or Section 2.4 above with respect to Expansion
Premises) as of the time in question and not deleted from the Premises pursuant
to Section 2.6 or 2.7 above, and (ii) unless otherwise specified in this Lease,
references to Tenant's Percentage Share shall mean the aggregate of all Tenant's
Percentage Shares shown on the Basic Lease Information applicable to the
Premises as of the time in question, prorated for partial Floors then comprised
in the Premises, if applicable. In addition, during such periods as a partial
Floor is comprised in the Premises, Base Rent applicable to such Floor shall be
prorated based on the ratio (expressed as a percentage) which the Rentable Area
contained in the partial Floor bears to the Rentable Area of such Floor.

                  3.2. Extension. Upon the terms and conditions specified in
this Section 3.2, Landlord grants to Tenant the


                                      -60-
<PAGE>   74
right to extend the Term with respect to all or a portion of the Premises as
specified below for the two (2) Extended Terms.

                           a. Exercise and Notice. Tenant shall exercise its
right to extend the Term under this Section 3.2 for not less than those Floors
then comprised in the Premises within Floors 2 - 17, and if Tenant exercises its
right to extend the Term for additional Floors above Floor 17 then comprised in
the Premises, such exercise shall be made for such additional Floors in
ascending order, commencing with the next highest Floor of the Premises above
Floors 2 - 17. If Tenant exercises its right to extend the Term under this
Section 3.2 for less than all of the Floors then comprised in the Premises, the
Floors as to which Tenant does not exercise such right shall, as of the
expiration of the Term or Extended Term then in effect applicable to such
Floors, be automatically deleted from the Premises. If Tenant shall determine to
exercise its right to extend the Term (or Extended Term then in effect) for the
Premises under this Section 3.2, it shall do so by giving written notice to
Landlord of such exercise (the "Tenant Extension Notice") not earlier than
twenty-four (24) months nor later than twelve (12) months prior to the earliest
Expiration Date of the Term (or Extended Term then in effect) applicable to a
Floor within the Premises for which the Tenant Extension Notice is given. If
Tenant so exercises its right, then within ten (10) months prior to each
Expiration Date (as to the initial Term), or expiration date of the first
Extended Term, as applicable, for the affected Floors, Landlord shall notify
Tenant of the non-binding, proposed terms and conditions upon which Landlord
would be willing to lease to Tenant the affected Floors in the Premises for the
applicable Extended Term (the "Landlord's Proposal Notice"). Within thirty



                                      -61-
<PAGE>   75
(30) days after receipt of Landlord's Proposal Notice, Tenant shall notify
Landlord whether Tenant desires to negotiate the terms and conditions upon which
the Premises would be leased to Tenant for the applicable Extended Term. The
failure of Tenant so to notify Landlord within such 30-day period shall
terminate Tenant's right with respect to the Extended Terms, and Tenant shall
have no further rights to extend the Term for any portion of the Premises.

                           b. Negotiation on Tenant Exercise. If, within the
30-day period specified in Section 3.2.a above, Tenant exercises its right to
negotiate, then promptly upon receipt of Tenant's exercise notice, Landlord and
Tenant shall negotiate in good faith for a period of ninety (90) days in an
attempt to agree upon the terms and conditions upon which the Premises would be
leased to Tenant for the applicable Extended Term.

                           c. Procedure on Failure to Agree After Negotiation.
If, for any reason whatsoever, in the sole discretion of either party and
without any liability for any failure to reach agreement, either party concludes
at the expiration of the 90-day period for negotiation under Section 3.2.b above
that any of the terms and conditions under negotiation are unacceptable to such
party, then the party so concluding shall promptly so notify the other party,
and Base Rent for the Extended Term shall be determined pursuant to this Section
3.2.c. Upon such failure of the parties to reach agreement with respect to the
first Extended Term, Base Rent for the first Extended Term shall be the higher
of (i) fair market renewal rent determined in accordance with Section 3.2.d
below, or (ii) the total of the Base Rent and Escalation Charges in effect for
each Floor in the Premises as of the day immediately


                                      -62-
<PAGE>   76
preceding the date that the first Extended Term commences with respect to each
Floor, with the Base Year (other than for Floor 2 which has no Base Year) with
respect to each Floor being the calendar year in which the first Extended Term
commences with respect to each such Floor. Base Rent for the second Extended
Term shall be the higher of (A) fair market renewal rent determined in
accordance with Section 3.2.d below, or (B) the Base Rent in effect for the
first Extended Term increased (but not decreased) by any increase in the
Consumer Price Index (or substitute index as hereinafter provided) between the
date the first Extended Term commenced with respect to each Floor and the date
the second Extended Term commences with respect to each Floor, by reference to
the Consumer Price Index published for the month immediately prior to such dates
(as the same may subsequently be adjusted by the "Bureau"), with the Base Year
remaining unchanged from the first Extended Term. For purposes hereof, the
Consumer Price Index means The United States Department of Labor, Bureau of
Labor Statistics ("Bureau"), Consumer Price Index (All Urban Consumers, All
Items, 1982-1984 = 100) for the Metropolitan Area of which San Francisco,
California, is a part. If the Consumer Price Index is discontinued or revised,
the Consumer Price Index shall mean the index designated as the successor or
substitute index by the Bureau, or its successor agency, and if none is
designated, a comparable index as reasonably determined by Landlord, which would
likely achieve a comparable result to that achieved by the use of the Consumer
Price Index. If the base year 1982-1984 of the Consumer Price Index is changed,
then the conversion factor specified by the Bureau, or successor agency, shall
be utilized to determine the Consumer Price Index.



                                      -63-
<PAGE>   77
                           d. Determination of Fair Market Renewal Rent.

                                  (i) Fair Market Renewal Rent Defined. As used
in this Section 3.2, "fair market renewal rent" means the annual base rent for
the Floors in the Premises as to which Tenant has exercised its right to extend
the Term for an Extended Term which a landlord, under no compulsion to lease,
would rent the Premises for such Extended Term and a tenant, under no compulsion
to lease, would rent the Premises for such Extended Term, taking into account
all relevant considerations in accordance with then customary appraisal
practices and standards for determining fair market renewal rent utilized by
members of the Appraisal Institute (or its successor organization), with a then
current senior designation of MAI (or then comparable designation), currently
certified under the continuing education program, and having at least ten (10)
years experience in appraising commercial office properties in the Downtown
Financial District, and utilizing, to the extent necessary or appropriate in
accordance with the foregoing standard, comparable transactions in Comparable
Buildings (but not other buildings in the Downtown Financial District). For
purposes of determining fair market renewal rent, no renewal or extension of a
lease of space in a Comparable Building shall be utilized if such space contains
material quantities of asbestos, such as asbestos fireproofing or in-slab
asbestos. Fair market renewal rent shall be determined for each Floor as of the
date the Extended Term for such Floor commences.

                                  (ii) Determination of Fair Market Renewal
Rent. If Landlord believes that fair market renewal rent is higher than the Base
Rent determined under clause (ii) or clause (B) of Section 3.2.c above, as
applicable, then within not


                                      -64-
<PAGE>   78
less than six (6) months prior to the date the Extended Term shall commence with
respect to a Floor or Floors in the Premises, Landlord shall deliver to Tenant
Landlord's estimate of fair market renewal rent. Landlord and Tenant shall
thereupon negotiate in good faith for not more than thirty (30) days in an
attempt to determine fair market renewal rent for such Floor or Floors. If they
are able to agree within such 30-day period, then the fair market renewal rent
shall be the amount so agreed upon. If they are unable to agree on fair market
renewal rent within such 30-day period, then within ten (10) days after the
expiration of such 30-day period, the parties shall deliver to each other
concurrently at a mutually agreeable place and time their respective final
written estimates of fair market renewal rent on which Landlord would be willing
to lease to Tenant such Floor or Floors, and Tenant would be willing to lease
such Floor or Floors from Landlord. If each party's final estimate of the fair
market renewal rent is the same, then fair market renewal rent shall equal such
estimate. If one party's final estimate of fair market renewal rent is ten
percent (10%), or less, higher than the other party's final estimate, then fair
market renewal rent shall equal the average of the two (2) final estimates. In
every other case, the fair market renewal rent, based on the 2 final estimates,
shall be determined by arbitration as provided below in Section 31.16, except
that Base Rent for the first Extended Term shall never be less than the amount
specified in clause (ii) of Section 3.2.c above, and Base Rent for the second
Extended Term shall never be less than the amount specified in clause (B) of
Section 3.2.c above, and the arbitrators conducting the arbitration under
Section 31.16 shall be so instructed. Should the determination of fair market
renewal rent not be


                                      -65-
<PAGE>   79
completed or agreed upon prior to the date upon which an Extended Term
commences, Tenant shall pay annual Base Rent equal to Landlord's final estimate
of fair market renewal rent made pursuant hereto. If after determination of fair
market renewal rent, the annual Base Rent is less than the amount previously
paid by Tenant for such period, Landlord shall pay the difference to Tenant
within thirty (30) days after the date of such determination, with interest
thereon calculated from the date of each payment of such Rent at the Prime Rate
plus 1%; and, if after determination of fair market renewal rent, the annual
Base Rent is more than the amount previously paid by Tenant for such period,
Tenant shall pay the difference to Landlord within thirty (30) days after the
date of such determination, with interest thereon calculated from the date of
each payment of such Rent at the Prime Rate plus 1%.

                           e. Conditions to Exercise. Tenant's right to extend
the Term for either Extended Term pursuant to this Section 3.2 is conditioned on
the following as of the date Tenant gives the Tenant Extension Notice: (i)
Tenant has not entered into an assignment of this Lease requiring Landlord's
consent, and Tenant (and its Affiliates) physically occupy at least sixty
percent (60%) of the Premises as to which Tenant has exercised the option for an
Extended Term; (ii) no monetary or other material default by Tenant remains
uncured after the giving of any applicable notice and the expiration of any
applicable cure period; and (iii) Tenant's net worth is not less than Four
Hundred Seventy-Five Million Dollars ($475,000,000.00), as evidenced by Tenant's
separate, unconsolidated audited financial statements with a clean and
unqualified opinion, delivered to Landlord by Tenant within twenty (20) days
after Landlord's


                                      -66-
<PAGE>   80
request at any time after the date Tenant gives the Tenant Extension Notice
(which audited financial statements shall have been issued not more than fifteen
[15] months prior to the applicable exercise date), except that if Tenant does
not meet the conditions specified in this clause (iii), Tenant may provide to
Landlord Additional Security in order to satisfy the conditions specified in
this clause (iii).

                           f. Lease For Extended Term. If Tenant extends the
Term for an Extended Term in accordance with the provisions of this Section 3.2,
then Tenant shall continue to lease the Premises for such Extended Term on all
of the terms and conditions of this Lease, except that (i) Base Rent for an
Extended Term shall be the Base Rent determined pursuant to the applicable
provisions of this Section 3.2, and (ii) the Base Year for the first and second
Extended Term shall be the Base Year for the first Extended Term as determined
in accordance with this Section 3.2. Landlord and Tenant shall enter into any
amendments to this Lease reasonably required by either Landlord or Tenant to
confirm the terms and conditions upon which Tenant shall continue to lease the
Premises for such Extended Term, including the Base Rent, the new Expiration
Date based on the Extended Term, and such other amendments as are reasonably
required to implement such Extended Term.

         4. Rent.

                   4.1. Obligation to Pay Rent. Tenant shall pay to Landlord the
Base Rent for each Floor in the Premises during the Term as set forth in the
Basic Lease Information commencing on the Rent Commencement Date as defined in
Section 1.1, except that: (i) if Tenant elects to accept delivery of a partial
Floor pursuant to Section 3.1.b above, the Rent Commencement Date shall


                                      -67-
<PAGE>   81
apply to each portion of such Floor when possession is delivered to Tenant
pursuant to Section 3.1.b above and the Base Rent for such portion of the Floor
so delivered to Tenant shall equal the amount obtained by dividing the Base Rent
for such Floor specified in the Basic Lease Information by the Rentable Area of
such Floor and multiplying such quotient by the number of feet of Rentable Area
contained within the portion of such Floor delivered to Tenant pursuant to
Section 3.1.b above; (ii) if Tenant is delayed in construction of its initial
Alterations to a Floor, or partial Floor, comprised in the Premises after
delivery of possession of such Floor, or partial Floor, to Tenant pursuant to
Section 3.1 above on account of Landlord's failure to comply with or cause
compliance with Requirements pursuant to Section 8.1 below, then the Rent
Commencement Date for the affected Floor, or partial Floor, shall be extended
one (1) day for each day by which Tenant is delayed in making its initial
Alterations on account of such failure; (iii) if an event of damage or
destruction covered by Article 12 below, or a taking covered by Article 13
below, occurs after the Delivery Date for a Floor, but prior to the Rent
Commencement Date, then the unlapsed portion of the period between the Delivery
Date and the Rent Commencement Date for such Floor shall be tolled until
completion by Landlord of repair and restoration of the Premises pursuant to
Articles 12 or 13, as applicable, and such period shall resume and be added to
the applicable Rent and Escalation Charges abatement period for Tenant to repair
and restore Alterations pursuant to Articles 12 or 13 below; and (iv) whenever
(A) Base Rent and Escalation Charges abate on account of damage, destruction or
taking pursuant to Articles 12 or 13 below, (B) Tenant is granted as part of
such Rent and Escalation Charges abatement a period


                                      -68-
<PAGE>   82
within which to repair and restore Alterations, and (C) Tenant is delayed in
construction of such Alterations on account of Landlord's failure to comply
with, or cause compliance with, Requirements pursuant to Section 8.1 below, the
period for such Rent and Escalation Charges abatement specified in Article 12 or
13, as applicable, shall be extended one (1) day for each day by which Tenant is
delayed in making such Alterations on account of such failure. Tenant shall also
pay to Landlord the Antenna Fee during the Term as applicable. Base Rent for
each Floor in the Premises shall be paid to Landlord, in advance, in equal
monthly installments, commencing on the Rent Commencement Date for each Floor in
the Premises, and thereafter on or before the first day of each calendar month
during the Term for each Floor in the Premises. The Antenna Fee shall be paid to
Landlord monthly in advance, commencing on or before the date determined
pursuant to Section 2.2 above, and thereafter on or before the first day of each
calendar month during the Term until termination of the Antenna lease pursuant
to Section 2.2. If the Rent Commencement Date and/or Expiration Date is other
than the first day of a calendar month, the installment of Base Rent for the
first and/or last fractional month of the Term shall be prorated on a daily
basis based on the actual number of days in the month.

                  4.2. Manner of Payment of Rent and Additional Charges. All
Rent and Additional Charges shall be paid by Tenant without notice, demand,
abatement, deduction or offset, except as otherwise specifically provided in
this Lease, in lawful money of the United States of America, and if payable to
Landlord, at Landlord's Address, or to such other person or at such other place
as Landlord may from time to time designate by notice to Tenant.


                                      -69-
<PAGE>   83
                  4.3. Additional Charges. All Additional Charges other than
Escalation Charges, if payable to Landlord shall, unless otherwise specified in
this Lease, be due and payable thirty (30) days after Tenant's receipt of
Landlord's invoice therefor.

                  4.4. Late Payment of Rent and Additional Charges; Interest.
Tenant acknowledges that late payment by Tenant of any Rent or Additional
Charges will cause Landlord to incur administrative costs not contemplated by
this Lease, the exact amount of which are extremely difficult and impracticable
to ascertain based on the facts and circumstances pertaining as of the Lease
Date. Accordingly, if any Rent or Additional Charges are not paid by Tenant when
due, Tenant shall pay to Landlord, with such Rent or Additional Charges, a late
charge equal to four percent (4%) of such Rent or Additional Charges. In
addition, any Rent or Additional Charges, other than late charges, due Landlord
under this Lease, if not paid when due, shall also bear interest from the date
due until paid, at the Lease Rate. Notwithstanding the foregoing, from and after
the date Tenant elects to make payment of Base Rent and Escalation Charges by
wire transfer to Landlord's account, and only for so long as and during such
periods as Tenant makes payment by wire transfer, such late charge and interest
shall not be payable by Tenant with respect to Base Rent or Escalation Charges
until the expiration of three (3) Business Days after the date such Rent or
Escalation Charges is due for the first two (2) times during each calendar year
of the Term, and for the first time during each calendar year of an Extended
Term; but after such first two (2) or first (as the case may be) late payments
of such Rent or Escalation Charges by Tenant, any such Rent or Escalation
Charges not paid by Tenant when due shall be subject to the late charge and


                                      -70-
<PAGE>   84
interest hereunder and Tenant shall be entitled to no grace period with respect
to the application thereof hereunder. The parties acknowledge that such late
charge and interest represent a fair and reasonable estimate of the
administrative costs and loss of use of funds Landlord will incur by reason of a
late Rent and Additional Charges payment by Tenant, but Landlord's acceptance of
such late charge and/or interest shall not constitute a waiver of Tenant's
default with respect to such Rent and Additional Charges or prevent Landlord
from exercising any other rights and remedies provided under this Lease.

                  4.5. Free Rent. Pursuant to the terms of that certain Seventh
Amendment to Office Lease, dated June 1, 1996, between Landlord and Tenant,
Tenant is to pay to Landlord the sum of Two Million Three Hundred Ninety-Three
Thousand Two Hundred Twenty-Nine and 64/100 Dollars ($2,393,229.64) (the
"Premium Rent"). During the final months of the last year (the "Free Rent
Period") of the initial Term applicable to each Floor of the Premises, Tenant's
obligation to pay Rent and Escalation Charges as to such Floor shall abate in an
amount equal to the product obtained by multiplying the Premium Rent actually
paid by Tenant, as such Premium Rent may be reduced (i) to reimburse Landlord
for any Rent and Escalation Charges payment defaults which may exist as of the
beginning of or during the Free Rent Period, and (ii) by any Free Rent
previously paid by Landlord to Tenant with respect to a Floor under clause (B)
below (the difference, if any, the "Free Rent"), times a fraction equal to the
Rentable Area contained in such Floor (or the Galleria Rentable Area, in the
case of Floor 2), divided by the Rentable Area and Galleria Rentable Area
contained in the Premises as of the date of the first abatement of Rent and
Escalation Charges as to a Floor


                                      -71-
<PAGE>   85
hereunder. The Free Rent Period for a Floor shall commence on the date which is
closest, in Landlord's reasonable judgment, to relieve Tenant from the payment
of Rent and Escalation Charges as to such Floor through the end of the Term
applicable to such Floor. If Tenant does not receive the full benefit of the
Free Rent as of the Expiration Date for a Floor, then within ten (10) days after
Tenant vacates and surrenders such Floor in accordance with the terms of this
Lease, Landlord shall pay to Tenant an amount equal to the remaining Free Rent
allocable to such Floor. If the Free Rent Period for a Floor is longer than the
Free Rent allocable to such Floor, then Tenant shall resume paying Rent and
Escalation Charges as to such Floor upon the exhaustion of the Free Rent. If (A)
this Lease is terminated in whole pursuant to the terms of Sections 12.3, 12.5,
13.1 or 17.2, then Landlord shall pay to Tenant the sum equal to the then
aggregate Free Rent within ten (10) days after the termination of this Lease,
and if (B) this Lease is terminated in part pursuant to the terms of Sections
12.5, 13.1 or 17.2, then Landlord shall pay to Tenant within ten (10) days after
the partial termination of this Lease the sum equal to the product obtained by
multiplying the then aggregate Free Rent times a fraction equal to the Rentable
Area contained in such Floor (or the Galleria Rentable Area in the case of Floor
2), divided by the Rentable Area and Galleria Rentable Area contained in the
Premises immediately prior to the date of such partial termination. Landlord's
payment of the amounts due under either clause (A) or (B) above shall be a
condition of Landlord's right to terminate this Lease pursuant to Sections 12.3,
12.5, 13.1 or 17.2. If Landlord terminates this Lease on account of Tenant's
default, the amount of any remaining Free Rent not abated against Rent and
Escalation Charges

                                      -72-
<PAGE>   86
hereunder shall be deducted from any damages awarded to Landlord on account of
such default.

         5. Calculation and Payments of Escalation Charges. During each full or
partial calendar year of the Term applicable to each Floor in the Premises
subsequent to the Base Year for such Floor, Tenant shall pay to Landlord
Escalation Charges in accordance with the following procedures, terms and
conditions:

                  5.1. Payment of Estimated Escalation Charges. Subject to the
provisions of Section 5.5, during December of the Base Year and December of each
subsequent calendar year, or as soon thereafter as practicable, Landlord shall
give Tenant notice of its estimate of Escalation Charges due for the ensuing
calendar year, except that for Floor 2 of the Premises, Landlord shall give
Tenant notice of its estimate of Escalation Charges for Floor 2 prior to the
Rent Commencement Date for Floor 2 for the remainder of the calendar year in
which such Rent Commencement Date falls, and thereafter in December of each
subsequent calendar year, or as soon thereafter as practicable. On or before the
first day of each month during such ensuing calendar year (and for Floor 2,
commencing with the Rent Commencement Date for Floor 2, on or before the first
day of each month during the calendar year in which the Rent Commencement Date
falls, and thereafter on or before the first day of each month during each
ensuing calendar year), Tenant shall pay to Landlord in advance, in addition to
Base Rent and any Antenna Fee, one-twelfth (1/12th) of such estimated Escalation
Charges, unless such notice is not given in December, in which event Tenant
shall continue to pay on the basis of the prior calendar year's estimate until
the month after such notice is given, and subsequent payments by Tenant shall be
based on Landlord's notice. Within thirty (30)


                                      -73-
<PAGE>   87
days after Landlord's notice, Tenant shall also pay the difference, if any,
between the amount previously paid for such calendar year and the amount which
Tenant would have paid through the month in which such notice is given, based on
Landlord's noticed estimate. If at any time Landlord reasonably determines that
the Escalation Charges for the current calendar year will vary from Landlord's
estimate, Landlord may not more than twice in any calendar year, by notice to
Tenant, revise its estimate for such calendar year, and subsequent payments by
Tenant for such calendar year shall be based upon such revised estimate. In
estimating Escalation Charges hereunder, Landlord shall act in a commercially
reasonable manner and shall base such estimates on the Complex's operating
history and reasonably projected future Building Operating Expenses, Galleria
Operating Expenses, and Real Estate Taxes.

                  5.2. Escalation Charges Statement and Adjustment. Within one
hundred twenty (120) days after the close of each calendar year, or as soon
thereafter as practicable, Landlord shall deliver to Tenant a statement of the
actual Escalation Charges for such calendar year, showing in reasonable detail
the Building Operating Expenses, Building Property Taxes, Galleria Operating
Expenses and Galleria Property Taxes comprising the actual Escalation Charges.
Each statement shall be broken down at least into the categories, as applicable,
set forth in Exhibit E. Such statement shall be certified by Landlord or its
agent as true and correct to the certifying party's knowledge. If Landlord's
statement shows that Tenant owes an amount less than the payments previously
made by Tenant for such calendar year, Landlord shall credit the difference
first against any sums then owed by Tenant to Landlord and then against the next
payment or


                                      -74-
<PAGE>   88
payments of Rent and Additional Charges due Landlord, except that if a credit
amount is due Tenant after termination of this Lease, Landlord shall pay to
Tenant any excess remaining after Landlord credits such amount against any sums
owed by Tenant to Landlord. If Landlord's statement shows that Tenant owes an
amount more than the payments previously made by Tenant for such calendar year,
Tenant shall pay the difference to Landlord within thirty (30) days after
delivery of the statement. Landlord shall have the right, for a period of two
(2) years after the end of a calendar year to which a statement of actual
Escalation Charges issued hereunder pertains, to correct such statement and
deliver such corrected statement to Tenant and, subject to Tenant's rights under
Section 5.4 below and the other provisions and limitations contained in this
Article 5, Tenant shall pay any additional Escalation Charges shown to be due by
such corrected statement within thirty (30) days after receipt of Landlord's
corrected statement; upon expiration of such 2-year period, Landlord shall have
no further right to correct such statement of actual Escalation Charges, and
such statement shall be conclusive and binding on Landlord; and if Landlord
fails to render a statement for Escalation Charges with respect to a calendar
year within two (2) years after the end of such calendar year, Tenant shall have
no obligation to make any payment shown to be due with respect to such calendar
year on any statement of Escalation Charges thereafter delivered. All statements
hereunder shall be conclusive and binding on Tenant two (2) years after the
issuance of such statement by Landlord unless Tenant objects to any item
thereon, in which event, Tenant shall have the inspection and/or audit rights
specified in Section 5.4 below.



                                      -75-
<PAGE>   89
                  5.3. Proration for Partial Year. If this Lease commences or
terminates as to a Floor (or portion of a Floor) other than on the first or last
day of a calendar year, respectively (other than due to Tenant's default), the
amount of Escalation Charges for such fractional calendar year for such Floor
(or portion of a Floor) shall be prorated on a daily basis based on the ratio
(expressed as a percentage) which the number of days elapsed in such fractional
calendar year bears to 365. Upon such termination, Landlord may, at its option,
calculate the adjustment in Escalation Charges prior to the time specified in
Section 5.2 above.

                  5.4. Tenant Audit Rights With Respect to Escalation Charges.
Landlord shall maintain such books and records as are necessary in order to
account properly for Building Operating Expenses, Building Property Taxes,
Galleria Operating Expenses and Galleria Property Taxes. Tenant shall have the
right, upon the terms and conditions specified in this Section 5.4, to inspect
and audit such books and records.

                           a. Audit Right and Procedures. Tenant shall have the
right to inspect and/or audit such books and records one (1) time with respect
to each calendar year during the Term, except that if Landlord issues a
corrected statement of Escalation Charges after issuance of its calendar year
statement of actual Escalation Charges pursuant to Section 5.2 above, then
Tenant shall have an additional one time right to inspect and/or audit such
books and records with respect to such corrected statement of Escalation
Charges. Tenant shall conduct any inspection or audit which Tenant is entitled
to conduct hereunder not later than two (2) years after the issuance of the
Escalation Charges statement as to which such inspection and/or audit right

                                      -76-
<PAGE>   90
pertains, except that (i) any inspection or audit which Tenant conducts with
respect to a Base Year shall be conducted not later than two (2) years after the
issuance of the Escalation Charges statement for the calendar year immediately
succeeding such Base Year, and (ii) any inspection or audit which Tenant
conducts with respect to a corrected statement of Escalation Charges issued by
Landlord under Section 5.2 above shall be conducted not later than one (1) year
after the issuance of such corrected statement of Escalation Charges, or the
expiration of the 2-year period under clause (i) above if then longer than 1
year. If Tenant has the right to inspect and/or audit Landlord's books and
records hereunder and Tenant desires to exercise such right, then Tenant shall
give Landlord notice thereof at least ten (10) Business Days prior to the date
Tenant intends to conduct such inspection and/or audit. All inspections and
audits hereunder shall be conducted in the office where Landlord's books and
records are then kept, during regular business hours, except that if Landlord's
books and records are maintained by Landlord at a location other than the
Complex, Landlord shall, upon written request by Tenant, make such books and
records available for inspection and audit hereunder at the Building manager's
office in the Complex. Landlord shall give Tenant and its representatives
hereunder prompt and reasonable access to Landlord's books and records during
the course of conduct by Tenant of any inspection or audit hereunder, and shall,
at Tenant's expense, make copies of such books and records when and to the
extent requested by Tenant. Any inspection or audit hereunder shall be conducted
by (A) a reputable certified public accountant or accounting firm (a "CPA") with
experience in conducting inspections and/or audits of operating expenses in


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office buildings or (B) employees of Tenant. No Tenant employee or CPA so
designated by Tenant shall be compensated on a contingency basis on the results
of the inspection or audit, and Tenant shall be solely responsible for all costs
and expenses of any inspection or audit undertaken by Tenant hereunder,
including all costs of copying such books and records at Tenant's request,
except that if Tenant's audit concludes (or, in the event of a dispute between
the parties regarding the results of such audit, the final determination made in
any proceeding with respect to such dispute concludes) that Building Operating
Expenses and Galleria Operating Expenses for the calendar year in question were
overstated in the aggregate by more than three percent (3%) and Landlord's
statement for actual Escalation Charges for such calendar year was consequently
overstated, then Landlord shall reimburse Tenant for all reasonable costs and
expenses of Tenant's audit hereunder, and Landlord shall bear its costs
hereunder. Landlord shall have the right to designate a representative to be
present with any Tenant employee or CPA during such periods they are conducting
inspections and/or audits hereunder. If Tenant's audit shows that the amount of
Escalation Charges for the calendar year which is the subject of the audit was
under- or overstated, and Landlord does not dispute the results of such audit,
then, within thirty (30) days after Tenant concludes its audit hereunder, the
parties shall make such adjustments and payments as are necessary or appropriate
accurately to reflect the actual amount of such Escalation Charges actually due
Landlord for such calendar year. If Tenant's audit shows that the amount of
Escalation Charges for the calendar year which is the subject of the audit
actually paid by Tenant was overstated, and Landlord disputes such conclusion,


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then Tenant shall promptly supply to Landlord a copy of such portions of any
written report or analysis resulting from such inspection or audit which forms
the basis of Tenant's determination hereunder.

                           b. Confidentiality Requirements. Tenant shall keep
confidential as a trade or business secret all information resulting from any
inspection or audit undertaken by or on behalf of Tenant hereunder, and shall
impose by written agreement in the form attached hereto as Exhibit F-1, such
confidentiality requirement on any employee or third person conducting any
inspection or audit hereunder. Tenant may, however, disclose such information
(i) to the extent required by any applicable governmental law, ordinance, rule
or regulation; (ii) in any litigation or proceeding between the parties with
respect to any dispute between them regarding Escalation Charges (subject to
such protective orders to prevent disclosure and protect the confidentiality of
such information as may be available in accordance with applicable law, to which
Tenant hereby consents and shall not oppose); (iii) to the extent required by
judicial process (such as a subpoena duces tecum), after notice by Tenant to
Landlord of the receipt of such judicial process, and subject to Landlord's
right to seek such protective orders to prevent disclosure and protect the
confidentiality of such information as may be available in accordance with
applicable law (to which Tenant hereby consents and shall not oppose); (iv) if
such information is generally known to the public or is in the public domain,
other than on account of a breach by Tenant of its obligations under this
Section 5.4.b; or (v) to Tenant's executives, accountants, attorneys and other
agents and representatives (subject, however,


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<PAGE>   93
to the imposition on such executives, accountants, attorneys and other agents
and representatives, by written agreement in the form attached as Exhibit F-1,
the confidentiality requirements of this Section 5.4.b).

                           c. Limits on Right. The right of Tenant to inspect or
audit Landlord's books and records hereunder shall not be transferrable to or
inure to the benefit of any sublessee of Tenant. In no event shall Tenant have
any rights of inspection or audit hereunder if, but only during the period that,
Tenant is in monetary default under this Lease and such default remains uncured
after the giving of any required notice and expiration of any applicable cure
period. Tenant's rights of inspection or audit hereunder shall, in each instance
as applicable, be reinstated when and if Tenant cures any such monetary default.

                  5.5. Certain Limitations With Respect to Estimates of
Escalation Charges. Notwithstanding anything to the contrary contained in this
Article 5, Landlord may not increase estimated Escalation Charges for a calendar
year by more than one hundred five percent (105%) of the amount of the actual
Escalation Charges for the preceding calendar year, except for those items
included in Escalation Charges which will increase by more than one hundred five
percent (105%) due to clearly ascertainable circumstances or actual knowledge of
Landlord on account of being fixed recurring costs, extraordinary non-recurring
costs or noncontrollable costs (such as rates charged by public utilities,
insurance premiums, Real Estate Taxes, planned capital improvements, salary or
wage increases under union contracts, or increases scheduled in, or on account
of renegotiation of, service contracts for the Complex). Until the Escalation
Charges


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<PAGE>   94
for the preceding year is determined by Landlord, Landlord shall have the right
to base increases in estimated Escalation Charges, subject to the limitations of
this Section 5.5 and the provisions of Section 5.1, on the amount of the
estimated Escalation Charges for the preceding calendar year and when the actual
Escalation Charges is determined by Landlord for the preceding calendar year,
Landlord shall submit to Tenant the final calculation of estimated Escalation
Charges pursuant to the provisions of this Section 5.5 and the provisions of
Section 5.1, and the parties shall make such adjustments and payments as are
necessary or appropriate in order to reflect the amounts required to be paid by
Tenant on account of estimated Escalation Charges for the affected calendar
year. Landlord shall not collect as Building Operating Expenses and Galleria
Operating Expenses an amount that would reimburse Landlord for a sum in excess
of one hundred percent (100%) of actual Building Operating Expenses and Galleria
Operating Expenses in any calendar year. Landlord shall not recover any Building
Operating Expenses or Galleria Operating Expenses more than once.

                  5.6. Certain Limitations on Real Estate Taxes; Contest of Real
Estate Taxes; Contest of Impositions.

                           a. Limitations. Notwithstanding anything to the
contrary contained in this Lease, if the assessed value of the Complex (or any
portion thereof) is increased as part of Real Estate Taxes (under Article XIII A
of the California Constitution [commonly referred to as "Proposition 13"] or
otherwise) by reason of a conveyance or other "change in ownership" (as defined
in the California Revenue and Taxation Code) of the Complex (or any portion
thereof) during the period commencing as of September 1, 1999, through and
including August 31, 2002, then only after



                                      -81-
<PAGE>   95
the end of the third year of the Term may Landlord include in Real Estate Taxes
the full amount of such increase in assessed value and, prior to the expiration
of such third year of the Term, Landlord may only include that portion of such
increase in assessed value in each of the first three (3) years of the Term, as
applicable, derived by multiplying such increase by a fraction, the numerator of
which is the number of years then elapsed in the Term minus one (1), and the
denominator of which is three (3). In addition to the foregoing, if any
Impositions are imposed upon Tenant during a Base Year, which Impositions are
enacted in lieu of then existing Real Estate Taxes, the amount of Real Estate
Taxes included in such Base Year shall be adjusted to include such Impositions
paid by Tenant directly.

                           b. Contest of Real Estate Taxes. In determining
whether to contest any Real Estate Taxes comprised in Escalation Charges,
Landlord shall act in a commercially reasonable manner, taking into account all
relevant factors in making such decision. Tenant may from time to time after
issuance of a notice of assessed value of the Complex for an ensuing tax year,
but before a right to contest such assessed value expires, inquire of Landlord
in writing whether Landlord intends to contest such assessed value. Landlord
shall respond to Tenant's request within five (5) Business Days after receipt of
such request. Landlord shall have no liability to Tenant, however, for damages,
costs and/or expenses of any kind or character on account of Landlord's
declination to contest any Real Estate Taxes comprised in Escalation Charges,
regardless of whether Landlord has acted in a commercially reasonable manner,
Tenant waives and relinquishes any claims or rights to such damages, costs and
expenses, and Tenant's sole remedy shall be an


                                      -82-
<PAGE>   96
action or proceeding specifically to enforce Landlord's obligation hereunder to
act in a commercially reasonable manner, or enjoin Landlord's actions contrary
to such obligation. The cost of any contest of Real Estate Taxes shall be
included in Real Estate Taxes in accordance with the definition of Real Estate
Taxes set forth in Article 1.

                           c. Contest of Impositions. Tenant shall have the
right, upon the terms and conditions of this Section 5.6.c, to contest any
Impositions payable by Tenant under this Lease. If Tenant determines to contest
any such Impositions, Tenant shall so notify Landlord and either make payment of
such Impositions directly to the levying authority under protest prior to the
due date therefor, or if such Impositions are included in the tax bill to
Landlord and paid by Tenant to Landlord pursuant to Article 6 below, require
that Landlord make payment of such Impositions under protest. Tenant may
prosecute such contest in Tenant's name, or in Landlord's name if required by
applicable law, and Landlord shall cooperate with Tenant in prosecuting such
contest, executing such documents and instruments as may be necessary or
appropriate for Tenant to pursue such contest. Landlord's cooperation hereunder
shall, however, be without cost or expense to Landlord and Tenant shall bear all
costs and expense of any contest initiated and conducted by Tenant hereunder. If
at any time payment of any contested Impositions hereunder is required or
necessary in order to avoid termination or forfeiture of this Lease or the
interest of Landlord in the Complex, then Tenant shall promptly make such
payment, and if Tenant fails so to do, then Landlord shall have the right to
make such payment on behalf of Tenant and Tenant shall promptly reimburse
Landlord for all amounts paid by


                                      -83-
<PAGE>   97
Landlord, together with interest at the Prime Rate plus 1% from the date
Landlord makes such payment until the date Tenant repays such amount to
Landlord. Upon completion of any contest of Impositions conducted by Tenant
hereunder, Tenant shall pay all amounts (including penalties, interest, fines
and increases in Impositions) determined to be due on account of such contest.
Tenant shall indemnify, defend, protect and hold Landlord harmless from and
against any and all liability, loss, claim, cause of action, damages, cost or
expense (including reasonable attorneys' fees) arising out of or in connection
with, or incurred by Landlord on account of, any contest of Impositions
conducted by Tenant hereunder.

                 5.7. Adjustment of Base Year Operating Expenses for Certain
Insurance Items. If Landlord elects not to carry earthquake insurance pursuant
to Section 14.2 below for a Base Year applicable to a Floor in the Premises (or
as to Floor 2, in the year in which the Rent Commencement Date falls for Floor
2), but after such Base Year (or as to Floor 2, after the year in which the Rent
Commencement Date falls) Landlord elects to take out and carry such earthquake
insurance, then the amount of Building Operating Expenses and Galleria Operating
Expenses for such Base Year (or as to Floor 2, in the year in which the Rent
Commencement Date falls for Floor 2), as applicable, shall be increased by an
amount equal to the actual premium which Landlord pays for such earthquake
insurance in the calendar year in which such earthquake insurance is taken out.
If, after Landlord elects to take out such earthquake insurance, Landlord elects
to discontinue such insurance, then the Building Operating Expenses and/or
Galleria Operating Expenses for the affected Base Years hereunder (or as to
Floor 2, the year in which the Rent


                                      -84-
<PAGE>   98
Commencement Date falls) shall be reduced by the amount previously increased
pursuant to the preceding sentence. The adjustments to Base Year Building
Operating Expenses and/or Galleria Operating Expenses shall be effected in each
instance in which the circumstances specified in this Section 5.7 pertain.

                  5.8. Dispute Resolution. Any dispute between the parties with
respect to any matter under this Article 5 (including a dispute arising from any
inspection or audit conducted by Tenant pursuant to Section 5.4 above) shall be
resolved by arbitration pursuant to Section 31.17 below.

         6. Impositions Payable by Tenant. Tenant shall pay all Impositions
prior to delinquency. If billed directly, Tenant shall pay such Impositions and
on Landlord's request concurrently present to Landlord satisfactory evidence of
such payments. If any Impositions are billed to Landlord or included in bills to
Landlord for Real Estate Taxes, then Landlord shall deliver Landlord's invoice
therefor at least forty (40) days prior to the delinquency date, and Tenant
shall pay all such amounts to Landlord not later than ten (10) days prior to the
delinquency date. Landlord shall pay any such Impositions billed to Landlord
prior to delinquency and, if Landlord fails to do so, Landlord shall pay any
penalties or interest thereon due on account of payment after the delinquency
date thereof. If applicable law prohibits Tenant from reimbursing Landlord for
an Imposition, but Landlord may lawfully increase the Base Rent to account for
Landlord's payment of such Imposition, the Base Rent payable to Landlord shall
be increased to net to Landlord the same return without reimbursement of such
Imposition as would have been received by Landlord with reimbursement of such
Imposition.


                                      -85-
<PAGE>   99
         7. Use of Premises.

                  7.1. Permitted Use. The Premises shall be used solely for the
Permitted Use and for no other use or purpose. For purposes of the Permitted Use
of photocopying facilities which may be located by Tenant on Floor 2 Building
and/or Floor 3 of the Premises, such photocopying facilities shall be limited to
reproduction of materials primarily for the in-house use of Tenant and its
Affiliates, and not for external distribution in volume or in bulk to third
persons. As ancillary uses included within the Permitted Use, Tenant shall have
the right to use the Premises, other than Floor 2 Galleria, for the following
purposes, subject to the space limitations specified with respect thereto and
compliance by Tenant with all other applicable provisions of this Lease,
including this Article 7 and provisions for the making of Alterations to the
Premises: computer rooms occupying not more than 18,590 feet of Rentable Area;
auditoriums and classrooms for training employees of Tenant and Tenant's
Affiliates occupying not more than 37,180 feet of Rentable Area; a cafeteria for
employees and guests of Tenant and Tenant's Affiliates occupying not more than
10,000 feet of Rentable Area; a branch securities brokerage office providing
services and/or advice to employees of Tenant and Tenant's Affiliates with
respect to the purchase and sale of, or investment in, securities and other
investment vehicles, occupying not more than 10,000 feet of Rentable Area; a
travel agency providing travel services, advice and sales for employees of
Tenant, Affiliates of Tenant, and other agents of Tenant, occupying not more
than 10,000 feet of Rentable Area (in addition to any travel agency constituting
a Permitted Use on Floor 2 Galleria); an outlet for the sale of clothing items
to employees of Tenant, employees of Tenant's


                                      -86-
<PAGE>   100
Affiliates, and other agents of Tenant, bearing Tenant's logo and/or
identification or the logo and/or identification of Tenant's Affiliates,
occupying not more than 5,000 feet of Rentable Area; a fitness and exercise
center for employees of Tenant and Tenant's Affiliates, and other agents of
Tenant, occupying not more than 10,000 feet of Rentable Area; and trading floors
for the conduct by Tenant and Tenant's Affiliates of the purchase and sale of,
or investment in, securities and other investment vehicles occupying not more
than 74,360 feet of Rentable Area. All such uses ancillary to the Permitted Use
shall be located within Floors 2-15 of the Premises, and no such ancillary use
shall be permitted in any Floor of the Premises above Floor 15.

                  7.2. No Violation of Legal and Insurance Requirements. Tenant
shall not do or permit to be done, or bring or keep or permit to be brought or
kept, in or about the Premises, or any other portion of the Complex, anything
which (i) is prohibited by or will in any way, conflict with any Requirements
applicable to the Complex; (ii) would invalidate or be in conflict with the
provisions of any insurance policy carried by Landlord or Tenant on any portion
of the Complex or Premises, or any property therein; or (iii) would cause a
cancellation of any such insurance, increase the existing rate of or affect any
such Landlord's insurance, or subject Landlord to any liability or
responsibility for injury to any person or property, or give rise to any defense
in an insurer to any claim under, or result in a conflict with, any policies for
such insurance; or (iv) will in any way obstruct or interfere with the rights of
other tenants or occupants of the Complex, or injure or annoy them. Tenant shall
not bring onto any Floor of the Premises any furniture, fixtures


                                      -87-
<PAGE>   101
and/or equipment, and/or make any Alterations to any Floor in the Premises, the
aggregate weight of which would exceed the specified live load capacity of such
Floor, unless Tenant appropriately increases the live load capacity of such
Floor pursuant to Section 10.5 below. If Tenant does or permits anything to be
done which increases the cost of any of Landlord's insurance, or which results
in the need, in Landlord's reasonable judgment, for additional insurance by
Landlord or Tenant with respect to any portion of the Complex or Premises, then
Landlord shall promptly notify Tenant upon acquiring knowledge of such
circumstance. Tenant shall either (A) cease the activity causing such
circumstance within ten (10) days after receipt of Landlord's notice or (B)
reimburse Landlord for any such additional premiums or costs, and/or procure
such additional insurance at Tenant's sole cost and expense. In any event, if
Tenant elects to cease such activity, Tenant shall reimburse Landlord for any
such additional premiums or costs that Landlord shall have incurred prior to
Tenant's cessation of such activity. Invocation by Landlord of such right shall
not limit or preclude Landlord from prohibiting Tenant's impermissible use that
gives rise to the additional insurance premium or requirement or from invoking
any other right or remedy available to Landlord under this Lease. Landlord
acknowledges in connection with the provisions of this Section 7.2 that, as of
the Lease Date, use and occupancy by Tenant of the Premises for the Permitted
Use (but not as to the uses ancillary thereto permitted under Section 7.1 above,
as to which Landlord makes no acknowledgement, representation or warranty) will
not violate any of the provisions of this Section 7.2.


                                      -88-
<PAGE>   102
         7.3. Compliance with Legal, Insurance and Life Safety Requirements.
Tenant, at its cost and expense, shall promptly comply with all Requirements
applicable to the Complex, the provisions of all recorded documents affecting
any portion of the Complex as of the Lease Date (including the Declaration of
Crocker Properties, Inc., regarding building electric lighting, recorded August
26, 1981, as modified by Amended and Restated Declaration, dated December 5,
1984, recorded December 5, 1984), all of which are listed in Exhibit G and all
reasonable life safety programs, procedures and rules implemented or promulgated
by Landlord. Notwithstanding the foregoing, Tenant shall not be required to make
any capital improvements pursuant to this Section 7.3 except to the extent they
are necessitated by (i) Tenant's use or occupancy of, or business conducted in,
the Premises under Requirements enacted, promulgated or imposed directly on
occupants of space in office buildings (as distinguished from Requirements
imposed generally on office buildings as such) or Tenant's particular use,
manner of use or occupancy of the Premises (as distinguished from general
corporate and administrative offices as such), (ii) any default by Tenant under
this Lease, (iii) Alterations, or (iv) the installation, operation and/or
maintenance of the Antenna and/or Generator. Tenant shall promptly furnish to
Landlord any notices received from any insurance company, inspection bureau or
governmental agency regarding any non-compliance under this Section 7.3, or
regarding any unsafe or unlawful conditions within the Complex. The judgement of
any court of competent jurisdiction, or the admission of Tenant in any action or
proceeding involving Tenant, whether or not Landlord is party thereto, that
Tenant is in non-compliance with respect to any

                                      -89-
<PAGE>   103
matter specified in this Section 7.3 shall be conclusive of that fact.

         7.4. No Nuisance. Tenant shall not (i) do or permit anything to be done
in or about the Premises, or any other portion of the Complex, which would
injure or annoy, or obstruct or interfere with the rights of, Landlord or other
occupants of the Complex, or others lawfully in or about the Complex; (ii) use
or allow the Premises to be used in any manner inappropriate for a Class A
office building, or for any improper or objectionable purposes; or (iii) cause,
maintain or permit any nuisance or waste in, on or about the Premises, or any
other portion of the Complex.

         7.5. Compliance With Environmental Laws; Use of Hazardous Materials.
Without limiting the generality of Section 7.3 above, Tenant shall at all times
comply with all applicable provisions of Environmental Laws with respect to the
use and occupancy of the Premises or any portion of the Complex pursuant to this
Lease. Tenant shall not generate, store, handle, release or transport, or
otherwise use, or allow the generation, storage, handling, release or
transport, or other use of, Hazardous Materials in the Premises or transport
the same through the Complex, except that Tenant may use, store, handle and
transport Hazardous Materials as part of its business operation conducted
therein in the ordinary course as part of a Class A office building in the
Downtown Financial District, in accordance with the standards of this Article 7
(such as the use and storage of small quantities of office supplies which may
contain minor amounts of Hazardous Materials, the use of products containing
minor amounts of Hazardous Materials for the making of Alterations, the use of
products containing customary amounts of

                                      -90-
<PAGE>   104
Hazardous Materials in the maintenance, operation and repair of the Premises, or
the use or storage of chemicals, such as chlorofluorocarbons [CFC's], in amounts
necessary for the operation of systems in the Premises such as ventilation and
air conditioning package units). In the event of a release of any Hazardous
Materials caused by the act or neglect of Tenant, Tenant shall promptly notify
Landlord and take such remedial actions as Landlord may deem necessary or
appropriate to abate, remediate and/or clean up the same to Landlord's sole
satisfaction. If so elected by Landlord by written notice to Tenant, Landlord
shall take such remedial actions on behalf of and at Tenant's sole cost and
expense. In any event, Landlord shall have the right, without liability to
Tenant, to direct and supervise Tenant's remedial actions and to specify the
scope thereof and specifications therefor. Tenant shall use, store, handle and
transport any Hazardous Materials hereunder in accordance with the applicable
requirements of Environmental Laws (including use by Tenant of its Environmental
Protection Agency manifest number), and shall notify Landlord of any notice of
violation of Environmental Laws which it receives from any governmental agency
having jurisdiction. As used herein, Tenant includes its employees, agents,
contractors, invitees, licensees and sublessees.

         7.6. Cost of Handicap Access and Life-Safety Code Compliance.
Concurrently with the making of the initial Alterations to a Floor pursuant to
Section 10.4 below, Tenant shall make those Alterations, if any, to such Floor
as are required under applicable handicap access and/or life-safety laws,
ordinances, rules, regulations and codes (including the Americans with
Disabilities Act of 1990), to bring the Floors

                                      -91-
<PAGE>   105
into compliance with such laws, ordinances, rules, regulations and codes, and
Tenant shall be entitled to reimbursement of the construction cost of such
Alterations (the "Code Compliance Costs") upon the terms and conditions set
forth in this Section 7.6. Upon completion of the effected Alterations, Tenant
shall present to Landlord an itemization (together with appropriate and adequate
supporting documentation) of the Code Compliance Costs. The amount of the Code
Compliance Costs for each Floor shall be amortized on a straight-line basis at
ten percent (10%) per annum over a twenty (20) year life, commencing with the
Delivery Date for each Floor. If this Lease terminates as to a Floor, in whole
or in part, for any reason prior to the last day of the last 20-year period for
which any Code Compliance Costs are being amortized hereunder, other than on
account of the default of Tenant under this Lease, then subject to the
conditions hereafter specified, (i) if this Lease terminates as to an entire
Floor, Landlord shall reimburse to Tenant the then remaining unamortized portion
of the Code Compliance Costs with respect to such Floor, or (ii) if this Lease
terminates as to only a portion of a Floor, Landlord shall reimburse to Tenant
the then remaining unamortized portion of the Code Compliance Costs with respect
to such Floor, pro-rata on the basis of the Rentable Area (or Galleria Rentable
Area if Floor 2) of such Floor. Landlord shall make reimbursement hereunder
within thirty (30) days after the date of termination of this Lease as to a
Floor. If Landlord terminates this Lease on account of Tenant's default, the
amount of any remaining unpaid Code Compliance Costs will be deducted from any
damages awarded to Landlord on account of such default.

         8.  Building Services.




                                      -92-
<PAGE>   106
            8.1. Maintenance of Complex. Landlord shall maintain and repair
the Complex (other than the Premises, and the premises of other tenants of the
Complex, to the extent Tenant and such tenants are obligated to maintain and
repair the same) in good order and condition, except for ordinary (but not
excessive) wear and tear and subject to Articles 12 and 13 in the case of damage
by casualty or condemnation. Any damage occasioned by the gross negligence or
willful misconduct of Tenant, or Tenant's employees, agents, contractors,
licensees or invitees, shall be repaired by Landlord at Tenant's expense.
Landlord's maintenance of, and provision of services to, the Building shall be
performed in a manner consistent with that of the Comparable Buildings.
Specifically, but without limiting the generality of the foregoing standard,
Landlord shall (except to the extent that such obligation is imposed on Tenant
under the applicable provisions of this Lease or imposed on other tenants of the
Complex under their leases and subject to reasonable rights of contest) comply
with all Requirements applicable to the Complex, including making all
alterations to the Premises or Complex required thereunder; to the extent such
obligation to comply with Requirements applicable to the Complex is imposed on
other tenants of the Complex under their leases, and the failure by such other
tenants to perform such obligations would interfere with the use or occupancy of
the Premises by Tenant, Landlord shall use commercially reasonable efforts to
cause such tenants to comply with such obligations; and Landlord shall use
commercially reasonable efforts to enforce obligations of other tenants of the
Complex to maintain and repair their premises. Landlord shall have the right in
connection with its maintenance of the Complex hereunder (i) to change the
arrangement and/or


                                      -93-
<PAGE>   107
location of, or make alterations or additions to, any Common Area amenity,
Common Area installation or improvement, or other parts of the Complex, and (ii)
to utilize portions of the Common Areas from time to time for entertainment,
displays, product shows, leasing of kiosks or such other uses that in Landlord's
sole judgment tend to attract the public, so long as such uses do not
unreasonably interfere with or impair Tenant's access to or use or occupancy of
the Premises.

         8.2. Building Standard Services. Landlord shall cause to be furnished
to Tenant: (i) tepid and cold water to those points of supply and in volumes
provided for general use of tenants in the Building; (ii) electricity not to
exceed the Wattage Allowance, on a monthly, non-cumulative basis, for lighting
and the operation of electrically powered office equipment in the Premises
during the period from 7:00 a.m. to 6:00 p.m. on weekdays, and 7:00 a.m. to noon
on Saturdays (except Building Holidays); (iii) heat, ventilation and air
conditioning to the extent reasonably required for the comfortable occupancy by
Tenant of the Premises during the period from 7:00 a.m. to 6:00 p.m. on weekdays
and 7:00 a.m. to noon on Saturdays (except Building Holidays); (iv) passenger
elevator service; (v) freight elevator service and adjacent loading dock use,
subject to then applicable Building standard procedures and scheduling; (vi)
lamp replacement for Building standard lights; (vii) restroom supplies; (viii)
window washing of the exterior Building windows (both inside and outside) at
least two (2) times per year at times determined by Landlord; (ix) janitor
service on a five (5) day per week basis (excluding Building Holidays), except
for portions of the Premises used for preparing or consuming food or beverages;
and (x) reasonable security for the Complex (but not

                                      -94-
<PAGE>   108
individually for Tenant or the Premises), except that Landlord shall not be
liable in any manner for any unauthorized or criminal acts of others or for any
direct, consequential or other loss or damage related to any malfunction,
circumvention or other failure of such security service, including with respect
to any cooperation or coordination, or failure thereof, of security personnel
pursuant to Section 19.2.b below. Landlord may establish in the Premises or
other portions of the Complex such measures as it deems necessary or appropriate
to conserve energy, including automatic switching of lights and/or more
efficient forms of lighting.

                  8.3. Interruption or Unavailability of Services; Abatement of
Rent and Additional Charges. Except to the extent due to the gross negligence or
willful misconduct of Landlord, or its employees, agents or contractors, and
except for the foregoing, regardless of the cause of such failure, Landlord
shall not be in default hereunder or liable for any damages directly or
indirectly resulting from, no constructive or other eviction shall be construed
to have occurred, and Tenant shall not be relieved from any of its obligations
under this Lease (except for abatement of Rent and Additional Charges as
hereinafter provided), by reason of failure to furnish or delay in furnishing
any maintenance or services under this Article 8. Landlord shall use reasonable
efforts promptly to remedy any failure or interruption in the furnishing of such
maintenance or services, except that if Tenant is prevented from using the
Premises, or a portion thereof, for the Permitted Use due to any such failure or
interruption, Landlord shall employ such measures (including the use of premium
time) in order to cure such failure or interruption at the earliest feasible
time, and the cost of


                                      -95-
<PAGE>   109
such measures shall be included in Building Operating Expenses and/or Galleria
Operating Expenses, as applicable. Landlord makes no warranty or representation
to Tenant regarding the adequacy or fitness of the heating, air conditioning or
ventilation equipment in the Complex or the Premises to maintain temperatures
that may be required for or because of any of Tenant's equipment which uses
other than the fractional horsepower normally required for standard office
equipment and Landlord shall have no liability for loss or damage suffered by
Tenant or others in connection therewith. Notwithstanding anything to the
contrary contained in this Section 8.3, upon any failure or interruption in the
furnishing of maintenance or services hereunder not due to the act or neglect of
Tenant, or any employee, agent, representative, contractor, licensee or invitee
of Tenant, which failure or interruption prevents Tenant from accessing, using
or occupying the Premises under this Lease, in whole or in part, Rent and
Additional Charges shall not be abated for the first five (5) consecutive
Business Days that such failure or interruption persists; but after the
expiration of such 5-day period, Rent and Additional Charges shall abate to the
extent such failure or interruption interferes with access to, or the use or
occupancy of, all or any part of the Premises under this Lease, until such
failure or interruption is remedied so as to permit access to, and/or the use
and occupancy of, the affected portion of the Premises. Such abatement shall be
based on the extent to which such failure or interruption interferes with access
to, or the use and occupancy of, the Premises; and if such failure or
interruption affects a Critical Area, and as a result of such failure or
interruption affecting such Critical Area Tenant is unable to conduct its
business in another portion


                                      -96-
<PAGE>   110
or portions of the Premises, the Rent and Additional Charges abatement
provisions hereunder shall pertain to all portions of the Premises, including
the Critical Area, rendered unusable by Tenant in the conduct of its business as
a result of such failure or interruption to such Critical Area until such
failure or interruption is remedied so as to permit access to and/or the use and
occupancy of the Critical Area and other affected portions of the Premises.

        8.4. Tenant's Use of Excess Electricity, Water, and Heating, Ventilation
and Air-Conditioning. Tenant shall not, without Landlord's prior consent,
install in the Premises (i) lighting, the aggregate monthly, non-cumulative
power usage of which exceeds the Lighting Wattage Allowance, or lighting,
equipment, and/or apparatus, the aggregate monthly, non-cumulative power usage
of which exceeds the Wattage Allowance, or which requires a voltage other than
120/208 volts single or three-phase, (ii) heat generating or heat sensitive
equipment, or (iii) supplementary air conditioning facilities (Landlord
consenting to Tenant's installation of such supplementary air conditioning
facilities if such facilities meet the other applicable requirements for
Landlord's consent pursuant to this Lease). Tenant shall not permit or allow
occupancy levels in excess of one person per one-hundred-seventy-five (175) feet
of Rentable Area on each Floor of the Premises. Upon Tenant's request, from time
to time and at any time during the Term, Landlord shall supply daily
supplemental air conditioning on a 24-hour a day basis throughout the Term, at
Tenant's cost and expense as provided in this Section 8.4, until Tenant notifies
Landlord in writing to discontinue such supplemental services. If, pursuant to
this Section 8.4, heat-generating equipment are



                                      -97-
<PAGE>   111
installed or used in the Premises, or if the Premises or fixtures therein are
reconfigured by Alterations, and such equipment, occupancy levels or Premises
reconfiguration affects the temperature otherwise maintained by the Building air
conditioning system, or if equipment is installed in the Premises which requires
a separate temperature-controlled room, Landlord may, at Landlord's election
after notice to Tenant or shall upon Tenant's request, install supplementary air
conditioning facilities in the Premises, or otherwise modify the ventilating and
air conditioning serving the Premises, in order to maintain the temperature
otherwise maintained by the Building air conditioning system or to serve such
separate temperature-controlled room. Tenant shall pay the cost of any
transformers, additional risers, panel boards and other facilities if, when and
to the extent required to furnish power for, and all maintenance and service
costs of, any supplementary air conditioning equipment or facilities or modified
ventilating and air conditioning, or for lighting and/or equipment the power
usage of which exceeds the standards set forth in Section 8.2 above or to which
Landlord consents pursuant to this Section 8.4. The capital, maintenance and
service costs of such facilities and modifications shall be paid by Tenant as
Additional Charges. Landlord, at its election and at its expense, may also
install and maintain an electric current submeter and/or water submeter
(together with all necessary wiring and related equipment) at the Premises to
measure the power and/or water usage of such lighting or equipment; and
Landlord, at its election and at Tenant's expense, may also install and maintain
an electric current submeter or water submeter (together with all necessary
wiring and related



                                      -98-
<PAGE>   112
equipment) at the Premises to measure the power and/or water usage of such
ventilation and air conditioning equipment.

         8.5. Provision of Additional Services. If Tenant desires services in
additional amounts or at different times than set forth in Section 8.2 above, or
any other services that are not provided for in this Lease, Tenant shall make a
request for such services to Landlord with such advance notice as Landlord may
reasonably require. If Landlord provides such services to Tenant, then Tenant
shall pay (i) Landlord's then prevailing unit charge to provide heating,
ventilation and air conditioning, (ii) Landlord's actual cost to provide
electricity, and (iii) Landlord's actual cost to provide any other services plus
an administrative fee equal to twenty percent (20%) of such actual costs, not
exceeding, however, Two Hundred Fifty Dollars ($250.00) with respect to each
request from Tenant for such services. Landlord shall in all events provide
electricity for lighting and operation of electrically powered office equipment
in the Premises during the period from 6:00 p.m. to 7:00 a.m. on weekdays, noon
to midnight on Saturdays, all day Sundays, and on Building Holidays, on receipt
by Landlord from an authorized Tenant representative of a telephonic request
therefor at the management office for the Complex. Tenant shall make payment of
amounts due hereunder within thirty (30) days after Tenant's receipt of
Landlord's invoice.

         8.6. Standards With Respect to Certain Services. The standards set
forth in this Section 8.6 shall govern the provision of certain Building
services delivered by Landlord under this Article 8.

              a.  Heating, Ventilation and Air Conditioning. The base Building
heat, ventilation and air conditioning system


                                      -99-
<PAGE>   113
is designed to provide a maximum air volume (i) delivered to Floor 2 of the
Premises of 12,066 cubic feet per minute, (ii) delivered to Floor 3 of the
Premises of 3,000 cubic feet per minute, (iii) delivered to each of Floors 4-18
included in the Premises of 12,066 cubic feet per minute, and (iv) delivered to
each of Floors 19-25 included in the Premises of 13,050 cubic feet per minute,
and with the temperature of air at the point of delivery of 55(degree)
Fahrenheit. Subject to the foregoing minimum performance criteria, Tenant shall
be solely responsible for ambient air temperature within the Premises from the
point of delivery of air to the Premises in accordance with the foregoing
performance criteria.

         b. Janitorial Specifications. Landlord has supplied to Tenant, and
Tenant has reviewed and approved, the specifications for janitorial service for
the Building currently utilized by Landlord, a copy of which is attached
hereto as Exhibit H (the "Janitorial Specifications"). Landlord shall use
commercially reasonable efforts to provide janitor service to the Premises in
accordance with the Janitorial Specifications, including responding in good
faith to any concerns or complaints Tenant may have with respect to Landlord
compliance with the Janitorial Specifications. Landlord shall have the right to
modify the Janitorial Specifications from time to time or at any time in order
to respond to requirements of union or other applicable contracts with respect
to the delivery of janitor service, or otherwise in connection with prevailing
market services, or the provision of janitor service to the Building in
accordance with the standard for operation and maintenance of the Complex
specified in this Article 8, but if Landlord intends to modify the Janitorial
Specifications, Landlord shall first


                                     -100-
<PAGE>   114
deliver such proposed modified Janitorial Specifications to Tenant and, if so
requested by Tenant, shall meet and confer with Tenant with respect to any
concerns Tenant may have arising from such proposed modifications to the
Janitorial Specifications. Subject to such meet and confer requirement,
Landlord's decision with respect to modifications of the Janitorial
Specifications shall be conclusive and binding on Tenant, so long as such
modifications do not diminish the level of janitorial service specified in the
Janitorial Specifications set forth in Exhibit H.

         c. Elevator Services. So long as Tenant leases at least one (1) Floor
in the lowrise elevator bank of the Building (serving Floors 2 - 15), or the
midrise elevator bank of the Building (serving Floors 15 - 25), Landlord shall
not dedicate to the exclusive use of any tenant of the Building use of any
passenger elevators in such elevator bank. Nothing in the foregoing shall,
however, limit Landlord's right to effect such exclusive dedication of an
elevator in the elevator bank serving the highrise portion of the Building above
Floor 25 to a tenant of the Building occupying space in such highrise portion of
the Building. Landlord shall not charge for freight elevator service, except for
the cost of a security guard stationed at the freight elevator when in use by
Tenant for its move in to the Premises after 6:00 p.m. and before 7:00 a.m. on
weekdays, after noon on Saturdays, all day Sundays and on Building Holidays.

         d. Tenant's Share of Services. In addition to specific provisions of
this Lease with respect to utilization by Tenant of Tenant's Percentage Share of
Building utilities and appurtenant facilities in the core on each Floor of the
Premises (such as risers, conduits and shafts), Tenant shall at all times


                                     -101-
<PAGE>   115
have the right to have allocated to Tenant Tenant's Percentage Share of such
utilities and appurtenant facilities, except that, to the extent that Tenant's
usage thereof exceeds the Building standard for such services pursuant to
Section 8.2 above, or other applicable provisions of this Lease, then the other
applicable provisions of this Article 8 and other applicable provisions of this
Lease shall govern Tenant's usage of such above Building standard utility usage
and use of appurtenant facilities.

                  8.7. Compliance With Environmental Laws; Use of Hazardous
Materials. Landlord shall at all times comply with all applicable provisions of
Environmental Laws with respect to the use and occupancy of any portion of the
Complex (except to the extent that Tenant is obligated for such compliance
pursuant to Section 7.5 above, and except to the extent such other tenants are
obligated for such compliance pursuant to their leases); and to the extent other
tenants of the Complex are obligated for such compliance pursuant to their
leases, Landlord shall use commercially reasonable efforts to cause compliance
by such tenants with such obligations. Landlord shall not generate, store,
handle, or otherwise use, Hazardous Materials in the Complex, except as part of
its business operation conducted therein in the ordinary course as part of Class
A office buildings in the Downtown Financial District in accordance with the
standards of this Article 8 (such as the use and storage of small quantities of
office supplies which may contain minor amounts of Hazardous Materials, the use
of products containing minor amounts of Hazardous Materials for the making of
alterations, the use of products containing customary amounts of Hazardous
Materials in the maintenance, operation and repair of


                                     -102-
<PAGE>   116
the Complex, or the use or storage of chemicals, such as chlorofluorocarbons
[CFC's] in amounts necessary, for the operation of Building systems). In the
event of a release of any Hazardous Materials caused by the act or neglect of
Landlord, Landlord shall take such remedial actions as Landlord may deem
necessary or appropriate to abate, remediate and/or clean up the same to
Landlord's sole satisfaction; and in the event of a release of any Hazardous
Materials caused by the act or neglect of other tenants of the Complex (other
than Tenant, in which case the provisions of Section 7.5 above shall apply),
Landlord shall use commercially reasonable efforts to take such remedial actions
as Landlord may deem necessary or appropriate either to abate, remediate and/or
clean up the same to Landlord's satisfaction or enforce the obligation of such
tenants to perform the same in accordance with the terms of their leases. In
addition, if any Hazardous Materials are at any time present in a Floor
comprised in the Premises and such presence was not caused by Tenant, or its
employees, agents or contractors, Landlord shall remediate, abate and/or remove
such Hazardous Materials in conformance with the requirements of Environmental
Laws with respect to such Hazardous Materials, except that if such Hazardous
Materials are asbestos containing materials ("ACM"), then (i) if such ACM is in
floor tiles, Landlord shall remove such floor tiles and flash patch the floor
after such removal to make the floor level, and (ii) if such ACM is located in
other components of the Premises, Landlord shall encapsulate and/or remove
and/or make such ACM inaccessible in accordance with the applicable requirements
of Environmental Laws with respect to such ACM. Landlord shall use, handle,
store and transport any Hazardous Materials hereunder in accordance with the
applicable requirements of Environmental Laws




                                     -103-
<PAGE>   117
(including use by Landlord of its Environmental Protection Agency manifest
number). Landlord warrants and represents to Tenant, based solely on the actual
knowledge of Agnes Wyman, the Building general manager, James G. Clifford, the
real estate broker negotiating this Lease, Joseph Dobronyi and Robert Hutchison,
as representatives of the joint venture partners of Landlord, as of the Lease
Date, that Landlord has no knowledge of the presence of any Hazardous Materials
within the physical improvements comprising the Complex (specifically excluding
the Land), other than as disclosed by the Phase I Report and except for the
Hazardous Materials referred to in this Section 8.7 permitted to be maintained
by Landlord in the Complex under this Section 8.7. As used herein, other than in
connection with the foregoing warranty and representation, Landlord includes its
employees, agents, and contractors.

         9.   Maintenance of Premises. Tenant shall, at all times during the
Term, at Tenant's cost and expense, keep the Premises in good condition and
repair, except for ordinary wear and tear, damage by casualty or condemnation,
and the maintenance and repair to be performed by Landlord pursuant to Section
8.1 above. Except as specifically set forth in this Lease, Landlord has no
obligation to alter, remodel, improve, repair, decorate or paint the Premises,
or any part thereof, or any obligation respecting the condition, maintenance and
repair of the Premises. Except as provided in Section 20.7 below, Tenant hereby
waives all rights, including those provided in California Civil Code Sections
1941 and 1942, or any successor statutes, to make repairs which are Landlord's
obligation under this Lease at the expense of Landlord or, except as otherwise
specifically provided in this Lease, to receive any setoff or abatement of Rent
and Additional Charges.




                                     -104-
<PAGE>   118
         10.  Alterations to Premises.

            10.1. Landlord Consent; Procedure. Tenant shall not make or permit
to be made any Alterations (including initial Alterations under Section 10.4
below) without Landlord's prior consent, which shall not be unreasonably
withheld in accordance with Section 31.8, except that (i) as to any Limited
Alterations, Landlord's consent may be withheld in Landlord's sole discretion,
except as hereinafter provided with respect to ceilings and lighting, (ii)
Tenant may make minor decorative or cosmetic improvements or alterations in the
Premises (such as hanging pictures, painting, carpeting, wall covering or
similar items) without first obtaining Landlord's prior consent, and (iii)
Tenant may make changes in the field to Alterations previously approved by
Landlord without first obtaining Landlord's prior consent so long as such field
change (A) is not a Limited Alteration, (B) is necessitated by field conditions
as encountered during the construction of the Alterations and is required to be
made in order to conform the Alterations to such condition, (C) is consistent
with the purpose and intent of plans and specifications for the Alterations
approved by Landlord, and so long as (D) the cost of such field change does not
exceed Five Thousand Dollars ($5,000.00) for a single field change, or Twenty
Thousand Dollars ($20,000.00) in the aggregate for all field changes, with
respect to the Alterations under construction. All Alterations shall be made in
accordance with Building standard procedures as then reasonably established by
Landlord and the provisions of this Article 10, except that (1) the limits of
liability of any commercial general liability insurance required to be carried
by Tenant's contractors shall not exceed the commercial general liability
insurance required to be carried by



                                     -105-
<PAGE>   119
Tenant under Section 14.1 below, (2) except for review and approval by Landlord
of initial Alterations pursuant to Section 10.4, Landlord shall render any
approval of Alterations hereunder within five (5) Business Days after Tenant's
request for approval for Alterations affecting one (1) Floor or less in the
Premises, within ten (10) Business Days after Tenant's request for approval for
Alterations affecting more than 1 Floor in the Premises, but less than three (3)
Floors in the Premises, and fifteen (15) Business Days after Tenant's request
for approval of Alterations affecting 3 or more Floors in the Premises, and (3)
in the event of any inconsistency between the terms and provisions of this Lease
and the terms and provisions of the Building standard procedures, the terms and
provisions of this Lease shall control. In making any Alterations, Tenant shall
not be required to use then Building standard installations (such as lighting or
doors), subject, however, to Landlord's right to require removal of certain
Alterations pursuant to Section 10.3 below, except that (I) if Tenant changes or
replaces a ceiling on a Floor, Tenant shall make such change or replacement
throughout such Floor using a 2' x 2' fine line grid lay-in tile or similar
ceiling system, and (II) Tenant may use paracube or ceiling pendant-mounted
uplight lighting systems on a Floor, and if such lighting systems utilize light
fixtures or other lighting devices which are not flush with the ceiling, such
fixtures or devices shall be installed at least fifteen feet (15') away from the
perimeter walls of such Floor. Notwithstanding that such Alterations may
constitute Limited Alterations, if Tenant utilizes a 2' x 2' fine line grid
lay-in tile or similar ceiling system on each Floor of the Premises and/or a
paracube or uplight lighting system on a Floor, then Landlord shall


                                     -106-
<PAGE>   120
not unreasonably withhold its consent to such Alterations hereunder, but any
other ceiling system or lighting system on a Floor (other than the then Building
standard lighting system) shall constitute a Limited Alteration as to which
Landlord may withhold its consent in its sole discretion. Tenant may perform its
Alterations during normal Building business hours so long as the performance of
such Alterations does not interfere with the use or occupancy of the Complex by
other tenants or Landlord's operation of the Complex, and does not produce noise
audible outside of the Premises, or fumes or odors.

                  10.2. General Requirements. All Alterations shall be made at
Tenant's cost and expense. Tenant shall be solely responsible for compliance
with all applicable Requirements in connection with all Alterations. Tenant
shall be responsible for the cost of any additional alterations required by
applicable Requirements to be made by Landlord to any portion of the Complex as
a result of Alterations. Tenant shall complete all Alterations with reasonable
effort as soon as possible after commencement of the work of constructing such
Alterations in order to cause the least disruption to Complex operations and
occupants. Upon completion of any Alterations, Tenant shall promptly supply to
Landlord as-built drawings and specifications showing the Alterations as made
and constructed in the affected portions of the Premises. In connection with
installing or removing Alterations, Tenant shall pay Landlord's reasonable,
actual, out-of-pocket costs incurred to review Tenant's plans, specifications,
working drawings, permit applications and permits, and in connection with
Landlord's response to, review of, or involvement in, field conditions, or
circumstances in the field, arising during the course of construction of
Alterations by Tenant, after notice by Landlord to Tenant of such



                                     -107-
<PAGE>   121
circumstances. Landlord shall not charge a fee over and above such reasonable,
actual out-of-pocket costs. Landlord may also hire a third party to review
Tenant's plans, specifications and working drawings, permit applications and
permits, and applications by Tenant for payment of Construction Allowances under
Section 10.4 below, in which event Tenant shall reimburse Landlord for the fees
and costs charged by such third party. If Tenant requests that Landlord (or its
agent) administer construction, installation and/or removal of Alterations,
Landlord shall provide to Tenant a quotation for a fee payable to Landlord for
such services and, if Tenant approves the amount of such fee, then Landlord (or
its agent) shall, to the extent requested by Tenant, provide administration of
such construction, installation and/or removal of Alterations, and Tenant shall
pay the amount of such fee for such administration within thirty (30) days after
receipt of Landlord's notice therefor. Landlord shall, in connection with
Alterations hereunder, submit to Tenant from time to time statements and
invoices of Landlord's reasonable, actual out-of-pocket costs and fees and costs
of such third party incurred by Landlord, together with appropriate
documentation supporting and evidencing such costs and fees. Tenant shall pay
the amount of such statements within thirty (30) days after receipt thereof from
Landlord hereunder. If Tenant is delayed in making Alterations on account of
Landlord's failure to comply with, or cause compliance with, Requirements
pursuant to Section 8.1 above, then Landlord shall promptly, using all due
diligence, correct such failure (or cause such failure to be corrected) as soon
as possible in order to minimize any delay in the making by Tenant of such
Alterations.




                                     -108-
<PAGE>   122
        10.3. Ownership and Removal of Alterations. All Alterations shall become
part of the Complex and shall be Landlord's property from and after the
installation thereof, and may not be removed or changed without compliance with
the applicable provisions of this Article 10. If, on or before the date Landlord
approves Tenant's plans and specifications (or other documentation) for any
Alterations, Landlord notifies Tenant that Landlord reserves the right to
require Tenant to remove Alterations specified in Landlord's notice because they
exceed or are different than the then customary building standard installations
in Class A office buildings within the Downtown Financial District, then
Landlord, on notice given to Tenant, prior to the expiration of the Term or
termination of this Lease, may require Tenant to remove any or all such
Alterations at Tenant's cost and expense and restore the Premises to the
condition existing immediately prior to the installation of such Alterations.
In addition, if with respect to Floors 4 and/or 5 of the Existing Premises and
prior to the applicable Delivery Date, Landlord has notified Tenant on or before
the date Landlord approved Tenant's plans and specifications (or other
documentation) for any Alterations to such Existing Premises that Landlord
reserves the right to require Tenant to remove Alterations specified in
Landlord's notice and made by Tenant in such Existing Premises because they
exceed or are different than the then customary building standard installations
in Class A office buildings within the Downtown Financial District, then
Landlord, on notice given to Tenant, prior to the expiration of the Term or
termination of this Lease, may also require Tenant to remove any or all such
Alterations at Tenant's cost and expense and restore such Existing Premises to
the condition existing immediately prior to the installation of such
Alterations.




                                     -109-
<PAGE>   123
Landlord and Tenant acknowledge that examples of the Alterations which exceed or
are different from such customary building standard installations are
installations such as raised floors, stairways, computer rooms, vaults, built-in
safes, kitchens exceeding one (1) kitchen on a Floor, air conditioning and
ventilation package units, private restrooms, and any non-Building standard
ceiling and lighting systems (except a 2' x 2' fine line grid lay-in tile or
similar ceiling system and/or a paracube or uplight lighting system as specified
in Section 10.1 above). In addition to the foregoing right of


                                     -110-
<PAGE>   124
Landlord to require Tenant to remove Alterations, Tenant shall also remove all
Alterations (except for the ceiling and/or lighting system referred to in the
preceding sentence) comprised in any uses ancillary to the Permitted Use
instituted by Tenant in the Premises pursuant to Section 7.1 above, unless
Landlord waives in writing such removal requirement prior to the expiration of
the Term or earlier termination of this Lease as to the affected Floor or Floors
in the Premises. Prior to the expiration of the Term with respect to a Floor, or
earlier termination of this Lease with respect to a Floor, comprised in the
Premises, Tenant shall remove all cabling in under-floor duct systems and in
telecommunication closets in such Floor, except that Tenant shall have no
obligation of cable removal if this Lease expires or terminates (other than on
account of Tenant's default) on the same date with respect to all Floors then
comprised in the Premises. If Tenant fails to effect removal of Alterations to
the extent required pursuant to the foregoing provisions, then Landlord may
remove such Alterations and perform such restoration and Tenant shall reimburse
Landlord for Landlord's cost and expense incurred to perform such removal and
restoration. Tenant shall repair at its cost and expense all damage to the
Premises or Complex caused by the removal of any Alterations. Subject to the
foregoing provisions regarding removal, all Alterations (including any above
Building standard improvements to the Premises) shall at the expiration of the
Term or termination of this Lease remain on the Premises without compensation to
Tenant. All disputes with respect to Landlord's decision to require removal of
Alterations under this Section 10.3 shall be resolved by arbitration pursuant to
Section 31.17.

         10.4. Landlord's Construction Allowance. Upon the terms and conditions
set forth in this Section 10.4, Landlord shall



                                     -111-
<PAGE>   125
provide to Tenant the Construction Allowances for each Floor in the Premises set
forth in the Basic Lease Information.

              a.    Construction Allowances for Existing Premises. Subject to
the satisfaction of the conditions set forth in Section 10.4.b, and except as
provided in Section 10.4.c below, Landlord shall pay to Tenant a portion of the
Construction Allowances for the Existing Premises up to the sum of One Million
Dollars ($1,000,000.00) on or after January 2, 1998, which payment shall be paid
by Landlord to Tenant on account of monies advanced prior to January 2, 1998, by
Tenant on Landlord's behalf for Alterations to the Premises owned by Landlord
pursuant to the provisions of Section 10.3 above. Subject to the satisfaction of
the conditions set forth in Section 10.4.b, and subject to the provisions of
Section 10.4.c below, Landlord shall make such payment notwithstanding that the
Term has not yet commenced for any Floor in the Premises. After the date the
Term first commences for any Floor in the Existing Premises, Landlord shall pay
to Tenant such portions of the remaining amount of the Construction Allowances
for the Floors in the Existing Premises to the extent requested by Tenant
pursuant to Section 10.4.b below, provided that the conditions for disbursement
as set forth in Section 10.4.b have been satisfied and except as provided in
Section 10.4.c. Landlord's payment of the Construction Allowances for the
Existing Premises shall be made for certain Alterations which Tenant intends to
make, or has made (whether before or after the Lease Date), within the Existing
Premises, which include fees for architectural and engineering services and
construction and installation of Alterations.

               b.   Construction Allowances for Premises.


                                     -112-
<PAGE>   126
                    (i)  Payment of Construction Allowances. Except as provided
in Section 10.4.c below, and upon the terms and conditions specified in this
Section 10.4.b, Landlord shall provide to Tenant the Construction Allowances
with respect to each Floor in the Premises. Upon completion by Tenant of the
Alterations which Tenant makes to a Floor in the Premises in order to prepare
such Floor for use and occupancy, or continued use and occupancy, by Tenant for
the Permitted Use, Tenant shall submit to Landlord a statement setting forth all
costs and expenses incurred by Tenant for the design, construction and
installation of such Alterations on such Floor. Such statement shall be
accompanied by backup documentation adequate to evidence all such costs and
expenses (including contractor requisitions and requests for payment, invoices
and bills). Such statement shall also be accompanied by (i) a certificate of
Tenant's architect (or if none, an officer of Tenant) certifying that such
Alterations have been completed, (ii) final lien releases and waivers from all
contractors, subcontractors and suppliers performing work or supplying materials
for the Alterations, (iii) a certificate of final payment from all parties with
whom Tenant contracts directly for the design, construction and installation of
such Alterations, (iv) a notice of completion showing recording data filed in
accordance with applicable California mechanics' lien laws, (v) warranties (if
any are given to Tenant) against defects in workmanship, materials and
equipment, and (vi) a copy of the permits for such Alterations, signed by the
appropriate inspectors, indicating that such Alterations have been finally
approved. Upon approval by Landlord of Tenant's statement based thereon and all
the other documents and information supplied by Tenant, and subject to the
limitations on and provisions for payment set forth in Section 10.4.a with
respect



                                     -113-
<PAGE>   127
to the Existing Premises, Landlord shall pay to Tenant the amount of costs and
expenses incurred by Tenant for the design, construction and installation of
such Alterations up to, but not exceeding, the Construction Allowance for the
Floor in the Premises on which such Alterations were constructed and installed,
except that, by written notice from Tenant to Landlord, Tenant may elect to
allocate the Construction Allowance for one or more other Floors in the Premises
to the Floor or Floors on which such Alterations are to be performed, and the
affected Construction Allowances shall be so reallocated for use by Tenant in
connection with the making of such Alterations. In no event, however, shall the
aggregate Construction Allowances available to Tenant hereunder exceed the
aggregate total thereof for all Floors in the Premises as specified in the Basic
Lease Information. Subject to the provisions of Section 10.4.c below, if the
costs and expenses incurred by Tenant for the design, construction and
installation of the Alterations on a Floor in the Premises is less than the
Construction Allowance applicable to such Floor, then Tenant shall have the
right, at its election, either (A) to apply the unused portion of such
Construction Allowance to other Floors, or (B) to apply the unused portion of
such Construction Allowance, up to but not exceeding an amount equal to Ten
Dollars ($10.00) per square foot of Rentable Area contained in such Floor,
against the Rent and Additional Charges otherwise payable by Tenant for such
Floor until the full amount of the Construction Allowance for such Floor has
been utilized.

                    (ii)  Alternative Procedure for Disbursement of Construction
Allowances. Tenant may request Landlord to disburse the Construction Allowance
applicable to a Floor (subject to Tenant's reallocation rights under Section



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10.4.b(i) above) on a progress payments basis as costs and expenses are incurred
by Tenant for the design and construction of such Alterations. If Tenant makes
such request, then from time to time, but not more often than once every thirty
(30) days during the design and construction of such Alterations, Tenant shall
submit all of the information specified under Section 10.4.b(i) above applicable
to a final payment request (except that the architect's or Tenant's officer's
certificate shall pertain to the portion of the Alterations then completed, lien
releases and waivers shall be conditional and partial for each draw request,
with unconditional, partial lien releases with respect to the prior month's
payment with each subsequent payment request, a contractor's application for
payment shall be submitted in lieu of a certificate of final payment, and the
requirements of clauses (iv) - (vi) of Section 10.4.b(i) shall not apply). Upon
approval by Landlord of Tenant's information, Landlord shall make payments to
Tenant of the amounts requested by Tenant in accordance with the provisions of
Section 10.4.b(i) above, subject to the terms and conditions and limitations
therein specified with respect thereto. If so requested by Tenant, Landlord
shall make disbursements hereunder directly to Tenant's contractor, except that
no such disbursement shall create any contractual or other relationship between
Landlord and such contractor, Landlord shall have no obligation or liability to
such contractor, and Tenant's contract with such contractor shall so provide.
Upon completion by Tenant of such Alterations, Tenant shall apply for any final
amounts due in accordance with the procedures of Section 10.4.b(i) above.

                    (iii) Scope of Landlord Approval Right. In connection with
Landlord's right to approve Tenant's submittals under Sections 10.4.b(i) and
(ii) above, Landlord shall not


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withhold approval if (i) Tenant submits all required documentation and
information, and (ii) all such required documentation and information properly
evidences the information or matter to which it pertains.

                                    (iv)  Use of Construction Allowances.
Tenant shall have the right to use and apply the Construction Allowances for all
costs and expenses incurred by Tenant for the design, construction and
installation of Alterations as herein specified (including architectural,
engineering and consultants' fees) and for any other architectural, engineering
and consultants' fees, attorneys' fees, moving expenses, furniture, fixtures and
equipment, communication installations and signage for initial occupancy by
Tenant of the Premises; and, for purposes of this Section 10.4, reference to
"Alterations" and "all costs and expenses incurred by Tenant for the design,
construction and installation of such Alterations" shall be inclusive of all of
the foregoing items, costs and expenses.

                         c.   Certain Conditions and Limitations on Construction
Allowances. Notwithstanding anything to the contrary contained in this Section
10.4, Tenant shall expend at least Fifteen Dollars ($15.00) per foot of Rentable
Area (or in the case of Floor 2, per foot of Galleria Rentable Area) of the
Construction Allowance for initial Alterations to all Floors of the New
Premises, and an average of Fifteen Dollars ($15.00) per foot of Rentable Area
of the Construction Allowance for initial Alterations to Floors 18-21 combined.
Landlord's obligation to disburse any Construction Allowance shall be
conditioned upon all of the following as of the date such disbursement is to be
made: (i) no monetary or other material default by Tenant remains uncured after
the giving of any required notice and the expiration of any


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applicable cure period; and (ii) Tenant's net worth as of the date of
disbursement is not less than One Hundred Seventy-Five Million Dollars
($175,000,000.00) as evidenced by Tenant's separate, unconsolidated audited
financial statements with a clean and unqualified auditor's opinion, delivered
to Landlord within 30 days after Landlord's request (which audited financial
statements shall have been issued not more than fifteen (15) months prior to the
applicable disbursement date), except that if Tenant does not meet the
conditions specified in this clause (ii), Tenant may provide to Landlord
Additional Security in order to satisfy the conditions specified in this clause
(ii). If either of the conditions specified in clauses (i) - (ii) do not
continue to be satisfied as of the date of disbursement of a Construction
Allowance, Landlord shall have no obligation to disburse such Construction
Allowance or any further Construction Allowances, except that if any default
under clause (i) is subsequently cured, notwithstanding the expiration of the
applicable grace period, then Tenant's right to payment of such Construction
Allowances and any future Construction Allowances, shall be reinstated, subject,
however, to continuing fulfillment of the conditions specified in clauses (i) -
(ii). If the only condition unfulfilled is the net worth test specified in
clause (ii) above, then Landlord shall have the right to disburse only that
portion of the Construction Allowances as Landlord in its sole discretion deems
prudent in relationship to Tenant's then net worth. If Landlord exercises such
right, then the monthly installments of Base Rent due from Tenant to Landlord
with respect to the Premises, for the period from the date Landlord exercises
such right until the end of the Term, shall be abated to the extent of the
amount equal to the amount of the undisbursed portion of the Construction
Allowances,


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amortized over the balance of the Term applicable to such Floors on a
straight-line basis, with interest at the Prime Rate plus 1%. If for any reason
Tenant fails to request payment of a Construction Allowance within twenty-four
(24) months after the last Delivery Date with respect to any Floor or partial
Floor in the Premises, then Landlord's obligation to make payment of such
Construction Allowance shall terminate and Tenant shall have no right to payment
of such Construction Allowance.

                    d.   Dispute Resolution; Remedy for Failure of Landlord to
Pay Construction Allowances. Any disputes between the parties under this Section
10.4 (including a dispute pursuant to which Landlord fails to make payment of
any Construction Allowance) shall be resolved by arbitration pursuant to the
provisions of Section 31.17 below. Notwithstanding the foregoing, if the dispute
involves a claim by Tenant that it is entitled to payment of a Construction
Allowance, or portion thereof, and Landlord has failed or refused to make such
payment, then Landlord's right to initiate arbitration of such dispute, or
defend itself in such arbitration, shall be conditioned upon payment by Landlord
of the disputed amount into an escrow in trust on behalf of Landlord and Tenant,
with a national banking association designated by Landlord, with instructions to
disburse such amount in accordance with the final decision of the arbitrators
made pursuant to Section 31.17 below. Any interest accruing on such escrowed
funds shall be paid to the prevailing party as determined by the final decision
of the arbitrators made pursuant to Section 31.17. If Landlord fails to make
such deposit into escrow within thirty (30) days after Tenant's demand for
making such deposit, then Tenant shall have the right to offset the amount of
the unpaid Construction Allowance against Rent and Additional Charges otherwise
due and payable under


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this Lease until the full amount of such Construction Allowance has been offset
against Rent and Additional Charges.

                    e.   Certain Other Requirements With Respect to Initial
Alterations to Premises. Subject to all applicable Requirements, Tenant shall
have the right to design and construct Alterations in phases on a fast-track
basis in order to complete such Alterations at the earliest feasible time, and
Landlord shall cooperate by approving plans and specifications as they are
produced and submitted by Tenant so that Tenant may commence construction of
Alterations before completion of all plans and specifications applicable to the
entirety of such Alterations, except that Landlord may withhold approvals or
other actions to the extent, in Landlord's reasonable judgment, the plans and
specifications are not sufficiently complete or such actions are premature with
respect to the actual design of or work of construction on such Alterations.
Notwithstanding anything to the contrary contained in this Lease or any then
applicable Building standard procedures for Alterations, any approval by
Landlord of initial Alterations under this Section 10.4 to three (3) Floors or
less at any one time shall be given or withheld within ten (10) Business Days
after Tenant's request for such approval, and otherwise within twenty (20)
Business Days after Tenant's request for such approval.

                  10.5. Right of Tenant to Make Certain Alterations to Complex.
Subject to the terms and conditions of this Section 10.5, Tenant shall have the
right to increase the live load capacity for each Floor in the Premises, and/or
to increase the supply of electricity to one or more Floors in the Premises by
the installation of additional panels, bus taps, wiring, risers and/or
transformers. In addition, Landlord may, in connection with rendering any
approvals with respect to such Alterations, require



                                     -119-
<PAGE>   133
that Tenant remove such Alterations upon expiration of the Term or earlier
termination of this Lease and restore the affected portion of the Complex to its
original condition. Specifically, but without limiting the generality of the
foregoing, Landlord may require Tenant to remove wiring from risers installed by
Tenant hereunder.

         11.  Liens. Tenant shall keep the Premises and the Complex free from
any liens arising out of any work performed or obligations incurred by or for,
or materials furnished to, Tenant at Tenant's initiation pursuant to this Lease
or otherwise. Prior to the commencement of, and during the progress of, any
Alterations, Landlord shall have the right to post and keep posted on the
Premises any notices provided by law or which Landlord may deem to be proper for
the protection of Landlord, the Premises and the Complex from such liens. If
Tenant fails to keep the Premises and/or the Complex free of any lien pursuant
to this Article 11, then Landlord may, after first giving notice to Tenant of
its intent so to do, take such actions at the expense of Tenant that Landlord
deems necessary or appropriate in its sole discretion to prevent, remove or
discharge such liens.

         12.  Damage or Destruction.

                 12.1. Duration of Repair. If the Premises, or any other portion
of the Complex, are damaged or destroyed by fire or other casualty, Landlord
shall, as soon as possible after the date of such damage or destruction, but in
no event later than thirty (30) days after the date of such damage or
destruction, identify three (3) independent general contractors and/or
consultants (each of which shall be qualified and competent and experienced in
estimating the time and cost necessary to repair, and extent of, such damage or
destruction and the cost necessary to repair any


                                     -120-
<PAGE>   134
Alterations also damaged or destroyed), and shall notify Tenant of the identity
of such three general contractors and/or consultants. Landlord's notice shall
include pertinent information with respect to the qualifications of each
identified general contractor and/or consultant to formulate an estimate for the
time required to repair such damage or destruction, and shall also disclose all
past business dealings between Landlord and such general contractors and/or
consultants during the 4-year period prior to such notice. Tenant shall, within
ten (10) days after receipt of Landlord's notice, designate by written notice to
Landlord which of the three general contractors and/or consultants identified in
Landlord's notice that Tenant desires to undertake the formulation of the
estimate of the time and cost necessary to repair, and extent of, such damage or
destruction, and the cost necessary to repair any Alterations also damaged or
destroyed. Upon receipt of Tenant's selection hereunder, Landlord shall retain
the designated general contractor and/or consultant, which general contractor
and/or consultant shall, as soon as possible after designation hereunder, but in
no event more than ninety (90) days after such damage, prepare a written report
setting forth such general contractor's and/or consultant's estimate of the time
and cost necessary to repair, and extent of, such damage or destruction and the
cost necessary to repair any Alterations also damaged or destroyed. Upon
completion of such written report, Landlord shall cause such general contractor
and/or consultant to deliver such report to Landlord and Tenant. For purposes of
this Article 12, "the time required to repair such damage or destruction" shall
include the time necessary to obtain all governmental permits and approvals to
effectuate such repair or reconstruction, and the time necessary to


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<PAGE>   135
commence and complete the work of repair or reconstruction of such damage or
destruction.

                  12.2. Obligation to Repair. If the written report of the
general contractor and/or consultant prepared pursuant to Section 12.1 concludes
that (i) the time required to repair such damage or destruction is less than one
(1) year from the date of such damage or destruction, and (ii) less than forty
percent (40%) of the Complex is damaged or destroyed, and (iii) the damage or
destruction is covered by insurance carried by Landlord pursuant to this Lease
or otherwise, or would have been covered by insurance required to be carried by
Landlord pursuant to this Lease but for Landlord's failure so to do, or (iv) the
event of damage or destruction to the Premises and/or the Complex is not covered
by insurance and such insurance was not required to be carried or actually
carried by Landlord pursuant to this Lease or otherwise, and the cost of repair
of such damage or destruction is Ten Million Dollars ($10,000,000.00) or less,
then (A) Landlord shall promptly commence and prosecute with due diligence to
completion repair of the Premises, and/or the portion of the Complex necessary
for Tenant's use and occupancy of the Premises, to substantially the condition
existing immediately before such damage or destruction, as permitted by and
subject to then applicable laws, ordinances, rules and regulations; (B) this
Lease shall remain in full force and effect; and (C) Base Rent and Escalation
Charges shall abate for such part of the Premises rendered by such damage and
destruction unusable or inaccessible by Tenant in the conduct of its business
during the time such part is so unusable or inaccessible and for the earlier of
(1) ninety (90) days after the date of substantial completion of repair by
Landlord to enable Tenant to make Alterations, or (2) the date Tenant first
resumes



                                     -122-
<PAGE>   136
the Permitted Use in the affected portion of the Premises, in the proportion
that the Rentable Area contained in the unusable or inaccessible part of the
Premises bears to the total Rentable Area of the Premises, except that if the
damage or destruction occurs to the Antenna Area, then only the Antenna Fee
shall abate until such Premises are restored for Tenant's use. There shall be no
abatement of Rent and Escalation Charges for any damage or destruction to the
Generator Area. For purposes of the Rent and Escalation Charges abatement
provisions of clause (C) above, if a portion of the Premises containing a
Critical Area is damaged or destroyed, and as a result of such damage or
destruction to such Critical Area Tenant is unable to conduct its business in
another portion or portions of the Premises, then the Rent and Escalation
Charges abatement provisions of clause (C) shall pertain to all portions of the
Premises (including the Critical Area) rendered unusable by Tenant in the
conduct of its business as a result of such damage or destruction to such
Critical Area until such Critical Area is repaired under this Article 12,
subject, however, to the provisions of clauses (1) and (2) of clause (C) above.
In addition, if any Critical Area is damaged or destroyed and Tenant so
requests, Landlord shall use premium time and expedited construction in order to
effect the repair of such Critical Area, and Tenant shall reimburse Landlord for
all costs and expenses incurred by Landlord for such premium time and expedited
construction, which reimbursement shall be made from time to time by Tenant to
Landlord within thirty (30) days after receipt by Tenant of Landlord's invoice
therefor.

                  12.3. Election on Certain Events. If (i) the written report of
the general contractor and/or consultant prepared pursuant to Section 12.1 above
concludes that (A) the time to



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<PAGE>   137
repair such damage or destruction will exceed one (1) year from the date of such
damage or destruction, or (B) forty percent (40%) or more of the Complex is
damaged or destroyed, or (ii) the event of damage or destruction to the Premises
and/or the Complex is not covered by insurance and such insurance was not
required to be carried or actually carried by Landlord pursuant to this Lease or
otherwise, and the cost of repair of such damage or destruction exceeds Ten
Million Dollars ($10,000,000.00), then in any such case Landlord may elect,
within thirty (30) days after receipt of the written report of the general
contractor and/or consultant retained pursuant to Section 12.1, to terminate
this Lease, which election shall be made by written notice by Landlord to Tenant
and shall be effective thirty (30) days after the date of giving such notice. If
the written report of the general contractor and/or consultant prepared pursuant
to Section 12.1 above concludes that (1) (I) the time to repair such damage or
destruction will exceed one (1) year from the date of such damage or
destruction, or (II) forty percent (40%) or more of the Complex is damaged or
destroyed, and (2) the Premises, or a portion thereof, is damaged or destroyed
and such damage or destruction is of such extent and nature so as to
significantly impair Tenant's business use of or access to the Premises, as
reasonably determined by Tenant, then in any such case Tenant may elect within
thirty (30) days after receipt of the written report of the general contractor
and/or consultant retained pursuant to Section 12.1, to terminate this Lease,
which election shall be made by written notice by Tenant to Landlord and shall
be effective thirty (30) days after the date of giving such notice. If neither
party terminates this Lease pursuant to this Section 12.3 within the time
periods herein specified, then Landlord shall repair the Premises or the portion
of the Complex necessary for


                                     -124-
<PAGE>   138
Tenant's use and occupancy of the Premises pursuant to the applicable provisions
of Section 12.2 above and Base Rent and Escalation Charges shall abate as
specified therein. If either party terminates this Lease, then this Lease shall
terminate as of the date of the event of damage or destruction, and all proceeds
of insurance maintained by Landlord shall be paid to Landlord, and all proceeds
of insurance maintained by Tenant shall be paid to Tenant, except for Tenant
insurance proceeds paid on account of Alterations paid for by Landlord (whether
through the Construction Allowances or otherwise) which insurance proceeds shall
be paid to Landlord.

                  12.4. Cost of Repairs. Landlord shall pay the cost for repair
of the Complex and all improvements in the Premises, other than Alterations, the
Antenna, and the Generator. Tenant shall pay the costs to repair Alterations,
the Antenna, and the Generator.

                  12.5. Damage at End of Term.  Notwithstanding anything to
the contrary contained in this Article 12, if the Premises, or any portion
thereof, are damaged or destroyed by fire or other casualty within the last one
(1) calendar year of the Term applicable to that portion of the Premises damaged
or destroyed, and the time required to repair such damage or destruction is more
than ninety (90) days from and after the date of such damage or destruction,
then either Landlord or Tenant shall have the right, in either's sole
discretion, to terminate this Lease as it relates to the Premises so damaged or
destroyed by notice to the other given within thirty (30) days after the date of
such event. Such termination shall be effective on the date specified in the
terminating party's notice to the other party, but in no event later than the
end of such 30-day period. If the Complex is damaged or destroyed by fire or
other casualty within the last one



                                     -125-
<PAGE>   139
(1) calendar year of the Term applicable to Floors 2-9, and the time required to
repair such damage or destruction is more than ninety (90) days from and after
the date of such damage or destruction, then either Landlord or Tenant shall
have the right, in either party's sole discretion, to terminate this Lease by
notice to the other given within thirty (30) days after the date of such event.
Such termination shall be effective on the date specified in the terminating
party's notice to the other party, but in no event later than the end of such
30-day period.

                 12.6. Proration of Rent and Additional Charges on Termination.
Upon termination of this Lease pursuant to this Article 12, Landlord shall
promptly refund to Tenant any Base Rent paid by Tenant for any period after the
date of such termination and shall promptly refund any Additional Charges after
the exact amount of such Additional Charges have been determined.

                 12.7. Waiver of Statutes. The respective rights and obligations
of Landlord and Tenant in the event of any damage to or destruction of the
Premises, or any other portion of the Complex, are governed exclusively by this
Lease. Accordingly, Tenant hereby waives the provisions of any law to the
contrary, including California Civil Code Sections 1932(2) and 1933(4) providing
for the termination of a lease upon destruction of the leased property.

         13.  Eminent Domain.

                 13.1. Effect of Taking. Except as otherwise provided in this
Article 13, if all or any part of the Premises is taken as a result of the
exercise of the power of eminent domain or condemned for any public or
quasi-public purpose, or if any transfer is made in avoidance of such exercise
of the power of eminent domain (collectively, "taken" or a "taking"), this Lease
shall terminate as to the part of the Premises so taken as of the



                                     -126-
<PAGE>   140
effective date of such taking. On a taking of a portion of the Premises, Tenant
shall have the right to terminate this Lease by notice to Landlord given within
ninety (90) days after the effective date of such taking, if the portion of the
Premises taken is of such extent and nature so as to materially impair Tenant's
business use of the balance of the Premises, as reasonably determined by Tenant.
Such termination shall be operative as of the effective date of the taking.
Landlord may terminate this Lease on a taking of any material portion of the
Complex if Landlord reasonably determines that (i) such taking is of such extent
and nature as to render the operation of the remaining Complex economically
infeasible or to require a substantial alteration or reconstruction of such
remaining portion, or (ii) the amount of the award payable to Landlord under
Section 13.2 below, after deducting all costs and expenses incurred by Landlord
in connection with such taking, is not sufficient to restore the Complex, and
(iii) in either case (i) or (ii), Landlord terminates all of the leases in the
Building which Landlord has the right to terminate as a result of such taking of
the Complex. Landlord shall elect such termination by notice to Tenant given
within ninety (90) days after the effective date of such taking, and such
termination shall be operative as of the effective date of such taking. Upon a
taking of the Premises which does not result in a termination of this Lease, (A)
the Base Rent shall thereafter be reduced as of the effective date of such
taking in the proportion that the Rentable Area of the Premises so taken bears
to the total Rentable Area of the Premises, except that there shall be no
reduction in Rent attributable to a taking of the Antenna Area, unless Tenant is
deprived of the use and enjoyment of the Antenna Area, in which event only the
Antenna Fee shall be reduced or



                                     -127-
<PAGE>   141
abated, and (B) each of Tenant's Percentage Shares as shown on the Basic Lease
Information shall be recalculated as of the effective date of such taking based
on the ratio of Rentable Area remaining in each Floor comprised in the Premises
as of the effective date of such taking bears to the total Rentable Area
remaining in the Building as of the effective date of such taking, except that
Tenant's Percentage Share for Floor 2 in the Premises shall be recalculated
based on Galleria Rentable Area. There shall be no reduction in Rent and
Escalation Charges as a result of any taking of the Generator Area.

                 13.2. Condemnation Proceeds. Except as hereinafter provided, in
the event of any taking, Landlord shall have the right to all compensation,
damages, income, rent or awards made with respect thereto (collectively an
"award"), including any award for the value of the leasehold estate created by
this Lease. No award to Landlord shall be apportioned and, subject to Tenant's
rights hereinafter specified, Tenant hereby assigns to Landlord any right of
Tenant in any award made for any such taking. Tenant may seek to recover, at its
cost and expense, as a separate claim, any damages or awards payable on a taking
of the Premises to compensate for the unamortized cost of any Alterations or
Tenant's personal property taken for interference with or interruption of
Tenant's business (other than goodwill), or for Tenant's removal and relocation
expenses.

                 13.3. Restoration of Premises and Complex. On a taking of the
Premises or Complex which does not result in a termination of this Lease,
Landlord and Tenant shall restore the Premises and/or Complex as nearly as
possible to the condition they were in immediately prior to the taking in
accordance with the applicable provisions and allocation of responsibility for
repair and



                                     -128-
<PAGE>   142
restoration of the Premises and the Complex on damage or destruction pursuant to
Article 12 above.

            13.4. Tenant Waiver. The rights and obligations of Landlord and
Tenant on any taking of the Premises or any other portion of the Complex are
governed exclusively by this Lease. Accordingly, Tenant hereby waives the
provisions of any law to the contrary, including California Code of Civil
Procedure Sections 1265.120 and 1265.130, or any similar successor statute.

         14.  Insurance.

            14.1. Liability Insurance. Landlord, with respect to the Complex, at
its cost and expense but subject to reimbursement as Escalation Charges, and
Tenant, at its cost and expense with respect to the Complex, shall each maintain
or cause to be maintained, throughout the Term, a policy or policies of
commercial general liability insurance with limits of liability not less than
Ten Million Dollars ($10,000,000.00) combined single limit. Such coverage may be
provided by a combination of commercial general liability and excess umbrella
policies. Landlord may from time to time, on at least thirty (30) days' prior
written notice to Tenant, require Tenant to increase the limits of liability on
Tenant's liability insurance when and if Landlord determines such increase is
required adequately to protect the parties named as insureds or additional
insureds under such liability insurance, and the limits of liability for
liability insurance for comparable tenants in the Comparable Buildings; and if
Tenant disputes the propriety or basis of such increase, such dispute shall be
resolved by arbitration pursuant to Section 31.17 below. Each policy shall
contain coverage for contractual liability, personal injury liability, and
premises operations, coverage deleting liquor liability exclusions, and, as to
Tenant's



                                     -129-
<PAGE>   143
insurance, fire legal liability (which liability need not be in the amount of
$10,000,000.00).

                  14.2. Landlord Casualty Insurance. Landlord shall maintain, or
cause to be maintained, at its cost and expense but subject to reimbursement as
Escalation Charges throughout the Term, a policy or policies of All Risk or
Special Form fire and casualty insurance insuring the full replacement cost of
the Complex (exclusive of foundations and excavations). If Landlord carries
earthquake insurance on the Complex, the amount of such insurance shall be based
on probable maximum loss with not less than a 5% deductible based on the full
replacement cost of the Complex.

                  14.3. Tenant Casualty Insurance. Tenant, at its cost and
expense, shall maintain or cause to be maintained throughout the Term, a policy
or policies of All Risk or Special Form fire and casualty insurance (including
sprinkler leakage and water damage coverage), insuring the full replacement cost
of all Alterations, the Antenna, the Generator and Tenant's moveable furniture,
equipment and trade fixtures and other personal property in the Premises.
Landlord (and any encumbrancer under Article 21 below whose name and address is
provided to Tenant by notice given pursuant to Article 27 below), shall be named
as a loss payee under such insurance. Tenant shall provide to Landlord in
connection with the initial issuance and the annual renewal of the policy or
policies of insurance carried by Tenant hereunder a certificate of the insurance
company issuing such policy that such policy provides full replacement cost
coverage to cover 100% of the actual cost which would be required to replace the
property covered by such insurance in the event of the occurrence of a risk
included within the coverage of such insurance.



                                     -130-
<PAGE>   144
                  14.4. Form of Policies. All liability insurance required by
this Article 14 shall be issued on an occurrence basis; and all insurance
required by this Article 14 shall be issued by companies with a Best & Company
rating of A-, VIII or better. Any insurance policy under this Article 14 may be
maintained under a "blanket policy", insuring other parties and other locations,
so long as the amount and coverage required to be provided hereunder is not
thereby diminished. Each party shall provide to the other certificates of
insurance certifying that the policies contain the provisions required
hereunder. Each party shall deliver such certificates to the other no later than
one (1) Business Day prior to the first Delivery Date to occur hereunder or, as
to Tenant, such earlier date as Tenant or Tenant's contractors, agents,
licensees, invitees or employees first enter the Premises and, upon renewal, not
less than one (1) Business Day prior to the expiration of such coverage. All
liability insurance shall provide (i) that the other party, and its managing
agent, any constituent member of such party, and any encumbrancer (as defined in
Section 21.1 below) as requested by Landlord, is designated as an additional
insured without limitation as to coverage afforded under such policy; (ii) for
severability of interests or that acts or omissions of one of the insureds or
additional insureds shall not reduce or affect coverage available to any other
insured or additional insured; and (iii) that Tenant's insurance is primary and
noncontributing with any insurance carried by Landlord. Each party's insurance
shall provide that the insurer agrees not to cancel or alter the policy without
at least thirty (30) days prior written notice to all additional insureds or
loss payees. All deductibles under policies of insurance required to be carried
by either party under this Article 14 shall be commercially reasonable under the



                                     -131-
<PAGE>   145
circumstances, subject to any deductibles specifically set forth in this
Article 14.

                  14.5. Tenant Right of Self-Insurance. Tenant shall have the
right to self-insure for any of the insurance required to be carried by Tenant
under this Article 14 if and so long as (i) the net worth of Tenant is Two
Hundred Million Dollars ($200,000,000.00), and (ii) the net current assets of
Tenant are not less than Fifty Million Dollars ($50,000,000.00), as shown by
Tenant's separate, unconsolidated audited financial statements delivered to
Landlord within thirty (30) days after written request from time to time while
such self-insurance is in effect (which audited financial statements shall have
been issued not more than fifteen [15] months prior to the applicable date).
Whenever Tenant elects to self-insure pursuant to this Section 14.5, Tenant
shall, for all purposes of this Lease (including Article 16 below), be deemed to
be carrying the insurance required to be carried by Tenant under this Article
14.

         15.  Waiver of Claims and Subrogation Rights. Landlord and Tenant, each
for itself, and, to the extent legally permissible and without affecting any
insurance maintained by such party, on behalf of its insurer, releases and
waives any right to recover against the other party for any liability for: (i)
loss or damage to property; (ii) any other direct or indirect loss or damage
caused by fire or other risks, which loss or damage would be covered by any "All
Risk" or "Special Form" policy of insurance or is otherwise insured; or (iii)
claims arising by reason of any of the foregoing, irrespective of any act or
neglect of such other party which may have contributed to such loss or damage.
Each party shall, to the extent such insurance endorsement is lawfully
available, obtain or cause to be obtained, for the benefit of the



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other party, a waiver of any right of subrogation which the insurer of such
party may acquire against the other party by virtue of the payment of any such
loss covered by such insurance.

         16.   Waiver of Liability and Indemnification.

               16.1.  Waiver and Release.  Except to the extent due to the
negligence or willful misconduct of Landlord and except to the extent otherwise
provided in this Lease, Landlord shall not be liable to Tenant or Tenant's
employees, agents, contractors, licenses or invitees for, and Tenant waives as
against and releases Landlord from, all claims for loss or damage to any
property or injury, illness or death of any person in, upon or about the
Premises and/or any other portion of the Complex, arising at any time and from
any cause whatsoever (including such claims caused in whole or in part by the
act, omission, or neglect of other tenants, contractors, licensees, invitees or
other occupants of the Complex or their agents or employees). In no event shall
Landlord be liable to Tenant for, and Tenant waives as against and releases
Landlord from, all claims for consequential damages (including lost profits)
arising from any cause whatsoever, including the negligence of Landlord, but
excluding the gross negligence or willful misconduct of Landlord. The waiver and
release contained in this Section 16.1 extends to the officers, directors,
partners, employees, agents and representatives of Landlord.

               16.2. Indemnification of Landlord. Except to the extent due to
the negligence or willful misconduct of Landlord, Tenant shall indemnify,
defend, protect and hold Landlord harmless of and from any and all loss, liens,
liability, claims, causes of action, damage, injury, cost or expense arising out
of or in connection with, or related to (i) the making of Alterations (other
than Alterations made by Landlord on behalf of Tenant), or (ii) injury



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to or death of persons or damage to property occurring or resulting directly or
indirectly from: (A) the use or occupancy of, or any occurrence in or the
conduct of business in, the Premises, including the use of the Antenna and/or
the Generator; (B) the use, generation, storage, handling, release, transport,
or disposal by Tenant or Tenant's employees, agents or contractors, of any
Hazardous Materials in or about the Premises or any other portion of the
Complex; (C) acts, neglect or omissions of Tenant, its officers, directors,
agents, employees, invitees or licensees, in or about any portion of the
Complex; (iii) the installation, operation, maintenance, repair, replacement or
removal of the Antenna in the Antenna Area, including any claims by third
parties that the installation, operation and/or maintenance of the Antenna
interferes with such third persons' telecommunication devices or equipment and
claims by third persons for bodily injury and/or property damage caused by the
installation, operation and/or maintenance of the Antenna; or (iv) the
installation, operation, maintenance, repair, replacement or removal of the
Generator in the Generator Area, including any claims by third parties that the
installation, operation and/or maintenance of the Generator interferes with such
third person's devices or equipment and claims by third persons for bodily
injury and/or property damage caused by the installation, operation and/or
maintenance of the Generator. Tenant's indemnity obligation includes reasonable
attorneys' fees and costs, reasonable investigation costs and all other
reasonable costs and expenses incurred by Landlord. Landlord shall have the
right to approve legal counsel proposed by Tenant for defense of any claim
indemnified against hereunder or under any other provision of this Lease, except
that if such counsel is appointed by an insurance company providing a defense to
Landlord and/or


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Tenant, then such counsel shall be deemed approved by Landlord. The
indemnification contained in this Section 16.2 shall extend to the officers,
directors, partners, members, employees, and agents of Landlord.

                  16.3. Indemnification of Tenant. Except to the extent due to
the negligence or willful misconduct of Tenant, Landlord shall indemnify,
defend, protect and hold Tenant harmless of and from any and all loss, liens,
liability, claims, causes of action, damage, injury, cost or expense arising out
of or in connection with, or related to (i) the making of Alterations by
Landlord on behalf of Tenant or the making of any other alterations or additions
by Landlord to the Complex, or any portion thereof, or (ii) injury to or death
of persons or damage to property occurring or resulting directly or indirectly
from: (A) acts, neglect or omissions of Landlord, its officers, directors,
agents, employees, invitees or licensees, in or about the Premises or any other
portion of the Complex; (B) the use, generation, storage, handling, release,
transport, or disposal by Landlord or Landlord's employees, agents or
contractors, of any Hazardous Materials in or about the Premises or any other
portion of the Complex; and (C) any other occurrence in or on the Complex,
excluding the Premises. Landlord's indemnity obligation includes reasonable
attorneys' fees and costs, reasonable investigation costs and all other
reasonable costs and expenses incurred by Tenant. Tenant shall have the right to
approve legal counsel proposed by Landlord for defense of any claim indemnified
against hereunder or under any other provision of this Lease, except that if
such counsel is appointed by an insurance company providing a defense to
Landlord and/or Tenant, then such counsel shall be deemed approved by Tenant.
The indemnification contained in this Section 16.3 shall extend to the




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directors, officers, partners, shareholders, members, employees, and agents of
Tenant.

         17.    Assignment and Subletting.

                17.1. Compliance Required. Except as otherwise provided in
Section 17.9 below, Tenant shall not, directly or indirectly, voluntarily or by
operation of law, sell, assign or otherwise transfer this Lease, or any interest
herein (collectively, "assign" or "assignment"), or sublet the Premises, or any
part thereof, or permit the occupancy of the Premises by any person other than
Tenant (collectively, "sublease" or "subletting", the assignee or sublessee
under an assignment or sublease being referred to as a "transferee"), without
Landlord's prior consent given or withheld (i) reasonably in accordance with
Section 31.8, and (ii) in accordance, and in compliance, with the express
standards, conditions and provisions of this Article 17. Any assignment or
subletting made in violation of this Article 17 shall be void. As used herein,
an "assignment" includes any sale or other transfer in one or more transactions
of a majority of the voting stock of Tenant, if Tenant is a privately held
corporation, or any sale or other transfer in one or more transactions of a
majority of the beneficial interests in Tenant, if Tenant is any other form of
privately-held entity. Tenant acknowledges that the limitation on assignment and
subletting contained in this Article 17 are expressly authorized by California
Civil Code Section 1995.010, et seq., and are fully enforceable by Landlord
against Tenant.

                17.2. Request by Tenant; Landlord Response. If Tenant desires
to effect an assignment or sublease, Tenant shall submit to Landlord a request
for consent together with the identity of the parties to the transaction, the
nature of the transferee's proposed



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business use for the Premises, the proposed documentation for and terms of the
transaction, and all other information reasonably requested by Landlord
concerning the proposed transaction, including financial information (certified
as accurate and complete by an authorized representative of the proposed
transferee), credit reports, and the general business history regarding the
transferee. Within twenty (20) days after the receipt of all such information
required by Landlord, or within thirty (30) days after the date of Tenant's
request to Landlord if Landlord does not request additional information,
Landlord shall, by notice to Tenant, either: (i) consent to the assignment or
sublease, subject to the terms of this Article 17; (ii) decline to consent to
the assignment or sublease; or (iii) terminate this Lease as to the affected
portion of the Premises as of the date specified by Tenant as the effective date
of the proposed assignment or sublease, in which event Tenant will be relieved
of all unaccrued obligations hereunder as to such portion as of such date, other
than those obligations which survive termination of this Lease. Notwithstanding
the provisions of this Section 17.2, Tenant shall have the right, each time
Tenant desires to assign this Lease or sublet a portion of the Premises and
prior to requesting Landlord's consent to an assignment or sublease, to notify
Landlord that Tenant desires to assign this Lease or sublet a portion of the
Premises. Tenant's notice shall set forth all material terms and conditions upon
which Tenant is willing to assign this Lease or sublet the affected portion of
the Premises. If Tenant gives Landlord such notice, then Landlord shall have the
right, by written notice to Tenant given within twenty (20) days after the
receipt of Tenant's notice, to terminate this Lease as to the Premises in the
case of an assignment, and the affected portion of the Premises in the case of a
sublease, in which event Tenant


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<PAGE>   151
will be relieved of all unaccrued obligations hereunder as to such portion of
the Premises as of such date, other than those obligations which survive
termination of this Lease. If Landlord does not exercise such right of
termination hereunder within such 20-day period, then Tenant shall have the
right to attempt to enter into an assignment or sublease substantially upon the
terms set forth in Tenant's notice to Landlord hereunder for a period of two
hundred seventy (270) days after the expiration of such 20-day period. If,
within such 270-day period, Tenant does not enter into an assignment or sublease
substantially on the terms and conditions set forth in Tenant's notice to
Landlord hereunder, then Tenant shall, if it intends again to attempt to assign
or sublease the affected portion of the Premises, notify Landlord of such intent
and the material terms and conditions upon which Tenant intends to attempt to
assign or sublease the affected portion of the Premises, and Landlord shall once
again have the right to terminate this Lease in accordance with the foregoing
provisions. In addition, if during such 270-day period, Tenant effects a change
in the terms and conditions set forth in the notice to Landlord hereunder so
that Tenant is no longer attempting to assign or sublet substantially on the
terms and conditions set forth in Tenant's notice to Landlord, then Tenant shall
promptly after effecting such change so notify Landlord and Landlord shall have
the right to terminate this Lease in accordance with the foregoing provisions
for the 20-day period therein specified and if Landlord does not exercise such
right of termination within such 20-day period, then Tenant shall have a new
270-day period to attempt to assign or sublet in accordance with such changed
terms and conditions. For purposes hereof, "substantially on the terms and
conditions set forth in Tenant's notice to Landlord" means that Tenant enters
into



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an assignment or a sublease with a third person on economic terms and
conditions not more favorable to the transferee than the equivalent of ninety
percent (90%) of the economic terms and conditions set forth in Tenant's notice,
and without material deviation with respect to the other terms and conditions
set forth in Tenant's notice.

                  17.3. Conditions for Landlord Approval. Without limiting the
grounds on which it may be reasonable for Landlord to withhold its consent to an
assignment or sublease, Tenant acknowledges that Landlord may reasonably
withhold its consent in the following instances: (i) if Tenant is in monetary or
other material default under this Lease after the giving of any required notice
and the expiration of any applicable cure period; (ii) if the transferee is a
governmental or quasi-governmental agency, foreign or domestic; (iii) if the
transferee is an existing tenant in the Building and space comparable to the
space in the Premises is then available in the Building for lease to such
existing tenant; (iv) if in Landlord's reasonable judgment the transferee's
business use and/or occupancy of the Premises would not be consistent with
tenancies then in the Building; (v) in the case of a sublease, it would result
in more than three (3) separately demised occupancies on a Floor in the
Premises, including Tenant and subtenants; and (vi) in the case of an
assignment, if, in Landlord's reasonable judgment, the financial condition of
the transferee is not commensurate with the obligations of the transferee to be
performed under this Lease. If Landlord consents to an assignment or sublease,
the terms of such assignment or sublease transaction shall not be modified
without Landlord's prior written consent pursuant to this Article 17. Landlord's
consent to an assignment



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<PAGE>   153
or subletting shall not be deemed consent to any subsequent assignment or
subletting.

                 17.4. Costs and Expenses. Unless Landlord terminates this Lease
as to the affected portion of the Premises pursuant to clause (iii) of Section
17.2 above, as a condition to the effectiveness of any assignment or subletting
under this Article 17 for which Landlord's consent is required, Tenant shall pay
to Landlord all reasonable out-of-pocket costs and expenses, including
attorneys' fees and disbursements, incurred by Landlord in evaluating Tenant's
requests for assignment or sublease, whether or not Landlord consents to an
assignment or sublease. If Landlord terminates this Lease as to the affected
portion of the Premises pursuant to clause (iii) of Section 17.2 above, then
Tenant shall have no liability for any costs or expenses under this Section
17.4.

                 17.5. Payment of Excess Rent and Other Consideration. Except as
otherwise provided in Section 17.9 below, Tenant shall also pay to Landlord,
promptly upon Tenant's receipt thereof, one hundred percent (100%) of any and
all rent, sums or other consideration (except sums paid for Tenant's personal
property sold or rented to the transferee), howsoever denominated, realized by
Tenant in connection with any assignment or sublease transaction in excess of
the Rent and Escalation Charges payable hereunder (prorated on a Rentable Area,
or Galleria Rentable Area as to Floor 2, basis to reflect the Rent and
Escalation Charges allocable to the portion of the Premises if a sublease),
after first deducting from or offsetting against such consideration Tenant's
out-of-pocket expenses incurred in connection with such assignment or sublease
(such as advertising and promotional expenses and attorneys' fees), any broker's
commission paid by Tenant in



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<PAGE>   154
connection with such assignment or sublease, any tenant improvement period not
exceeding ninety (90) days, granted to a subtenant during which such subtenant
is not obligated to pay rent, any allowances, tenant improvements, rent
concessions or other monetary concessions made by Tenant in connection with such
assignment or sublease, and any costs or expenses paid by Tenant pursuant to
Section 17.4 above.

                  17.6. Assumption of Obligations; Further Restrictions on
Subletting. Each assignee shall, concurrently with any assignment, assume all
obligations of Tenant accruing under this Lease after the effective date of the
assignment. Each sublease shall be made subject to this Lease and all of the
terms, covenants and conditions contained herein; and the surrender of this
Lease by Tenant, or a mutual cancellation thereof, or the termination of this
Lease in accordance with its terms, shall not work a merger and shall, at the
option of Landlord, terminate all or any existing subleases or operate as an
assignment to Landlord of any or all such subleases. No sublessee shall have the
right further to sublet, but a sublessee shall have the right, subject to the
applicable provisions of this Article 17, to effect a partial or full assignment
of its sublease upon such terms and conditions as Tenant and such sublessee may
provide in the sublease. Any assignment by a sublessee of its sublease, whether
partial or in full, shall be subject to Landlord's prior consent in the same
manner as a sublease by Tenant. No sublease, once consented to by Landlord,
shall be modified without Landlord's prior consent. No assignment or sublease
shall be binding on Landlord unless Tenant or the transferee delivers to
Landlord a fully executed counterpart of the assignment or sublease which
contains the assumption by the assignee, or recognition by the sublessee, of the
provisions of


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<PAGE>   155
this Section 17.6, but the failure or refusal of Tenant or a transferee to
deliver such instrument shall not release or discharge Tenant or such transferee
from the provisions and obligations of this Section 17.6.

                  17.7. No Release. No assignment or sublease shall release
Tenant from its obligations under this Lease, whether arising before or after
the assignment or sublease. The acceptance of Rent and Additional Charges by
Landlord from any other person shall not be deemed a waiver by Landlord of any
provision of this Article 17. On a default by any assignee of Tenant in the
performance of any of the terms, covenants or conditions of this Lease, Landlord
may proceed directly against Tenant without the necessity of exhausting remedies
against such assignee. No consent by Landlord to any further assignments or
sublettings of this Lease, or any amendment or termination of this Lease, or
extension, waiver or modification of payment or any other obligations under this
Lease, or any other action by Landlord with respect to any assignee or
sublessee, or the insolvency, or bankruptcy or default of any such assignee or
sublessee, shall affect the continuing liability of Tenant for its obligations
under this Lease and Tenant waives any defense arising out of or based thereon,
including any suretyship defense of exoneration, except that (i) if this Lease
is terminated for any reason other than the default of a transferee of Tenant or
Tenant, Tenant's liability for unaccrued obligations under this Lease shall
terminate as of the date of termination of this Lease, and (ii) Tenant shall
have no liability for any amendments or modification of this Lease made after
the date Tenant assigns this Lease to an assignee. Landlord shall have no
obligation to notify Tenant or obtain Tenant's consent with respect to any of
the foregoing matters.



                                     -142-
<PAGE>   156
                 17.8. No Encumbrance. Notwithstanding anything to the contrary
contained in this Article 17, Tenant shall have no right to encumber, pledge,
hypothecate or otherwise transfer this Lease, or any of Tenant's interest or
rights hereunder, as security for any obligation or liability of Tenant.

                 17.9. Certain Rights with Respect to Assignments and Subleases.

                       a. Right to Assign or Sublet without Landlord's Consent.
Notwithstanding the provisions of Section 17.1 above, the provisions of this
Article 17 shall not apply to the transfer of stock in Tenant so long as Tenant
is a publicly traded corporation whose stock is listed on a national or regional
stock exchange or over the counter stock exchange or to the issuance of stock in
Tenant in a public offering. Notwithstanding the provisions of Section 17.1
above, Tenant shall have the right to assign this Lease to, or sublet all or any
portion of the Premises to, or permit occupancy of the Premises by, an Affiliate
without Landlord's consent. The effectuation of any transaction shall be subject
to the limitations specified in clauses (i), (ii), (iv), (v) and (vi) of Section
17.3, and Sections 17.7 and 17.8, and require compliance with the provisions of
Section 17.6. Tenant shall not have an obligation to pay to Landlord the amounts
set forth in Sections 17.4 and 17.5 with respect to any such transaction.

                       b. Certain Rights to Sublet Without Landlord's Consent.
Notwithstanding the provisions of Section 17.1 above, upon the terms and
conditions specified in this Section 17.9.b, Tenant shall have the right to
sublet the Rentable Area contained in up to two (2) Floors within the Premises
without first obtaining Landlord's prior written consent. Tenant must sublease



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<PAGE>   157
all the Rentable Area on a single Floor hereunder before subleasing Rentable
Area on the second Floor hereunder. If Tenant enters into a sublease of any
Rentable Area hereunder, Tenant shall, promptly after entering into such
sublease, notify Landlord of such sublease transaction, the identity of the
parties to the transaction, the nature of the transferee's use and occupancy of
the Premises, and the documentation for and terms of the transaction. Any
sublease made by Tenant hereunder shall be subject to the limitations specified
in clauses (i) - (v) of Section 17.3 above, and in Sections 17.7 and 17.8. Each
sublease entered into by Tenant hereunder shall also be subject to, and Tenant
and the sublessee shall as applicable comply with, the provisions of Section
17.6. Tenant shall not have an obligation to pay to Landlord the amounts set
forth in Sections 17.4 and 17.5 with respect to any sublease entered into
hereunder. The provisions of this Section 17.9.b shall not apply to Floor 2
Galleria.

                    c. Recapture with Respect to Certain Subletting.
Notwithstanding the provisions of Section 17.2 above to the contrary, and in
addition to Tenant's right to sublease two (2) Floors pursuant to Section 17.9.b
above without Landlord's consent, Tenant shall have the right to sublease up to
an additional 18,590 feet of Rentable Area in the Premises, as to which
subleases Landlord shall have no right to exercise its termination rights under
Section 17.2 (but shall have all other rights under this Article 17) so long as
the term of such sublease is for the shorter of (i) five (5) years, or (ii) if
the remainder of the Term then in effect is less than five (5) years, for the
remainder of such Term, minus six (6) months. Subject to the foregoing
limitation, Landlord's right to terminate this Lease on a sublease of a portion
of the Premises pursuant to Section 17.2 shall pertain to all


                                     -144-
<PAGE>   158
subleases, other than those effectuated pursuant to Sections 17.9.a and 17.9.b
and this Section 17.9.c. The provisions of this Section 17.9.c shall not apply
to Floor 2 Galleria.

                         d. Non-disturbance of Certain Sublessees. If Tenant
subleases a portion of the Premises comprised in two (2) Floors or more, either
pursuant to Section 17.9.b above or otherwise pursuant to Landlord's consent
hereunder, Landlord shall, if so requested by Tenant, grant to such sublessee a
non-disturbance right in writing, if the following standards, terms and
conditions are met by the sublease transaction: (i) the sublease meets the
applicable terms and conditions of this Article 17; (ii) the sublessee agrees in
the event of a termination of this Lease, other than on account of damage or
destruction or taking covered by Articles 12 and 13 above, to attorn to Landlord
and assume all of Tenant's obligations under this Lease applicable to the
subleased premises, except as otherwise provided in clause (iii) below; (iii)
the sublessee agrees, in the event of a termination of this Lease from any
cause, other than on account of damage or destruction or taking covered by
Articles 12 and 13 above, to commence payment to Landlord upon such termination
of the higher of all rent and other amounts payable by such sublessee under its
sublease, or all Rent and Escalation Charges then and thereafter payable by
Tenant hereunder allocable to the subleased premises; (iv) that the sublessee
has agreed in writing that Landlord shall not be liable to the sublessee for any
default by Tenant under this Lease, regardless of whether such default results
in termination of this Lease; and (iv) if this Lease terminates on account of
damage or destruction or taking covered by Articles 12 and 13 above, Landlord
shall have the right, in its sole discretion, either to recognize the sublease
and such sublessee's rights thereunder and require the


                                     -145-
<PAGE>   159
sublessee to attorn to Landlord, upon the terms and conditions specified in
clauses (i) - (iii) above, or terminate such sublease. If such standards, terms
and conditions are met, then the provisions of Section 17.6 with respect to
Landlord's termination rights shall not apply to such sublease.

         18.   Rules and Regulations. Tenant shall observe and comply, and shall
cause its sublessees, employees, agents, contractors, licensees and invitees to
observe and comply, with the Rules and Regulations of the Complex, a copy of
which are attached as Exhibit I, and, after notice thereof in accordance with
Article 27 of this Lease, with all reasonable modifications and additions
thereto from time to time promulgated in writing by Landlord. Landlord shall not
be responsible to Tenant, or Tenant's sublessees, employees, agents,
contractors, licensees or invitees, for non-compliance with any Rules and
Regulations of the Complex by any other tenant, sublessee, employee, agent,
contractor, licensee, invitee or other occupant of the Complex. Subject to the
foregoing limitation, Landlord shall not discriminate against Tenant in
enforcing the Rules and Regulations of the Complex. If there shall be any
conflict between any of the Rules and Regulations of the Complex and this Lease,
the terms and provisions of this Lease shall govern and prevail.

         19.   Entry of Premises by Landlord.

               19.1. Right to Enter. After reasonable advance notice of not less
than twenty-four (24) hours (except in order to provide regularly scheduled or
other routine Building standard services or additional services requested by
Tenant, when no such notice shall be required and except for emergencies where
Landlord shall give notice to the extent feasible under the circumstances and,
in any event, as soon as possible after the occurrence of such



                                     -146-
<PAGE>   160
emergency), Landlord and its authorized agents, employees, and contractors may
enter the Premises to: (i) inspect the Premises to determine Tenant's compliance
with its obligations hereunder; (ii) exhibit the same to Landlord
representatives, prospective purchasers or lenders; (iii) exhibit Floors within
the Premises to prospective tenants within eighteen (18) months prior to the
expiration of the Term or Extended Term then in effect for such Floor; (iv)
supply any services to be provided by Landlord hereunder; (v) prior to
commencement of and during the progress of Alterations, post notices of
non-responsibility or other notices permitted or required by law; (vi) make
repairs or perform maintenance in or to, the Premises, and improvements or
alterations required to be made or performed by Landlord under this Lease or
necessary to be performed by Landlord in any other portion of the Complex or for
other tenants of the Complex, including building systems; or (vii) perform a
Tenant obligation in accordance with the terms of Section 20.5 below. Entry to
the Premises under clauses (i), (ii), (iii), (v), and (vii) shall be effected
only during reasonable times during normal Building hours from 7:00 a.m. to 6:00
p.m. on weekdays, and 7:00 a.m. to noon on Saturdays (except Building Holidays);
and entry effected under clauses (iv) and (vi) shall be effected at reasonable
hours. Landlord may also grant access to the Premises to government or utility
representatives, and bring and use on or about the Premises such equipment, as
reasonably necessary to accomplish the purposes of Landlord's entry, subject
however to all the provisions and limitations of this Article 19. If Tenant so
elects, Tenant may require that any representative of Landlord or other person
entering the Premises pursuant to this Section 19.1 be accompanied at all times
by an authorized representative of Tenant (except in



                                     -147-
<PAGE>   161
the case of an emergency, in which event only to the extent feasible under the
circumstances). Landlord shall have and retain keys with which to unlock all of
the doors in or to the Premises (excluding Tenant's vaults, safes and similar
secure areas designated in writing by Tenant in advance), and Landlord shall
have the right to use any and all means which Landlord may deem proper in an
emergency in order to obtain entry to the Premises, including secure areas. Keys
retained by Landlord hereunder shall be used solely for access to the Premises
to provide janitorial services and for access to the Premises in cases of an
emergency, including entry by Landlord's security personnel. Landlord shall
establish, and use commercially reasonable efforts to enforce, procedures to
ensure that any such keys are maintained in the exclusive possession and control
of Landlord and its designated representatives and are not lost or copied. When
not in use, keys retained by Landlord hereunder shall be kept in the office of
the general manager of the Complex, janitorial supervisor's office and/or fire
control center.

                  19.2. Certain Secure Areas; Cooperation with Tenant Security
Personnel.

                        a.  Secure Areas.  If Tenant designates by written
notice to Landlord any portion of the Premises as a "secure area", then Landlord
shall, in connection with any entry by Landlord effected pursuant to Section
19.1, abide by such rules, regulations and procedures as Tenant, in its sole
discretion, may from time to time establish with respect to entry to such secure
area, including limitation as to time of entry, purpose of entry (other than as
necessary for Landlord to perform its obligations under this Lease), and
controls by Tenant with respect to the conduct of such entry (including
accompaniment by designated representatives of



                                     -148-
<PAGE>   162
Tenant). Landlord shall have no liability to Tenant to the extent designation of
a portion of the Premises as a secure area prevents or inhibits Landlord from
performing its obligations otherwise to be performed under this Lease with
respect to such secure area in the Premises. The provisions of this Section 19.2
shall not apply to emergency-required immediate access to the Premises, except
to the extent practicable under the circumstances.

                           b.  Landlord's and Tenant's Security Personnel. Each
party's and its security personnel shall cooperate with the other party and its
security personnel in implementing the parties' respective security requirements
within or about the Premises and the Complex. Landlord's and Tenant's security
personnel shall communicate from time to time with respect to security issues
and give each to the other such notices as may be necessary or appropriate from
time to time, or at any time, under the circumstances with respect to
emergencies and other security-related matters as soon as possible after the
occurrence thereof.

              19.3.   Tenant Waiver of Claims. Landlord shall effect all
entries and perform all work hereunder in such manner as to minimize
interference with Tenant's use and occupancy of the Premises, including locating
and daily removing equipment from the Premises as necessary so to minimize
interference. So long as Landlord conforms to the foregoing requirement, Tenant
waives any claim for damages for any inconvenience to or interference with
Tenant's business, or any loss of occupancy or quiet enjoyment of the Premises,
or any other loss, occasioned by any entry effected or work performed under this
Article 19, and, subject to Section 8.3, Tenant shall not be entitled to any
abatement of Rent or Additional Charges by reason of the exercise of any such
right of entry or performance of such work. If Landlord fails to effect an


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entry or perform work hereunder in such manner as to minimize interference with
Tenant's use and occupancy of the Premises, then Tenant may pursue any claims it
may have for actual damages for any inconvenience to or interference with
Tenant's business, or any loss of occupancy or quiet enjoyment of the Premises,
or any other loss occasioned by such entry, but Tenant shall have no right to
claim any consequential damages on account thereof (including lost profits), and
Tenant specifically waives the right to make or assert a claim for such
consequential damages. No entry to the Premises by Landlord or anyone acting
under Landlord made in accordance with the terms of this Lease shall constitute
a forcible or unlawful entry into, or a detainer of, the Premises or an
eviction, actual or constructive, of Tenant from the Premises, or any portion
thereof.

              19.4. Scope of Emergencies. For purposes of this Article 19, an
"emergency" means an occurrence or situation presenting imminent danger to the
health or safety of persons or damage to property, or criminal activity or
unauthorized entry into the Premises requiring response by Building security
personnel.

         20.  Default and Remedies.

              20.1. Events of Default.  The occurrence of any of the following
events shall constitute a default by Tenant under this Lease:

                    a.   Non-Payment of Rent or Additional Charges.  Failure to
pay any Rent or Additional Charges when due.

                    b.   Unpermitted Assignment of Sublease.  An assignment or
sublease made in contravention of any of the provisions of Article 17 above.

                    c.   Abandonment. Abandonment of the Premises by Tenant for
more than one (1) year. For purposes hereof,



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"abandonment" means cessation by Tenant of the conduct of its business in the
Premises and removal from the Premises of the personal property, equipment and
furnishings used by Tenant in its business in the Premises, with the intent
never to return.

                    d.   Other Obligations. Failure to perform or fulfill any
other obligation, covenant, condition or agreement under this Lease.

                    e.   Bankruptcy and Insolvency. A general assignment by
Tenant for the benefit of creditors, the liquidation of Tenant, any action or
proceeding commenced by Tenant under any insolvency or bankruptcy act or under
any other statute or regulation for protection from creditors, or any such
action commenced against Tenant and not discharged within ninety (90) days after
the date of commencement; the employment or appointment of a receiver or trustee
to take possession of all or substantially all of Tenant's assets or the
Premises; the attachment, execution or other judicial seizure of all or
substantially all of Tenant's assets or the Premises, if such attachment or
other seizure remains undismissed or undischarged for a period of thirty (30)
days after the levy thereof; the admission by Tenant in writing of its inability
to pay its debts as they become due; or the filing by Tenant of a petition
seeking any reorganization, arrangement, composition, readjustment, liquidation,
dissolution or similar relief under any present or future statute, law or
regulation, the filing by Tenant of an answer admitting or failing timely to
contest a material allegation of a petition filed against Tenant in any such
proceeding or, if within ninety (90) days after the commencement of any such
proceeding against Tenant, such proceeding is not dismissed. For purposes of
this Section 20.1.e, "Tenant" means Tenant and any partner of Tenant, if Tenant
is a partnership,



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or any person or entity comprising Tenant, if Tenant is comprised of more than
one person or entity, or any guarantor of Tenant's obligations, or any of them,
under this Lease, but does not include an assignor of this Lease who is a
predecessor in interest to the then Tenant.

                  20.2. Notice to Tenant. Upon the occurrence of any default,
Landlord shall give Tenant notice thereof. If a time period is specified below
for cure of such default, then Tenant may cure such default within such time
period. The time periods provided below are exclusive of any other time periods
provided by law with respect to cure of any such default and Tenant hereby
waives any right under law now or hereinafter enacted to any other time period,
including the notices described in Code of Civil Procedure Sections 1161,
et seq.

                      a. Non-Payment of Rent or Additional Charges. For failure
to pay Rent or Additional Charges, within five (5) Business Days after
Landlord's notice to Tenant.

                      b. Other Obligations. For failure to perform any
obligation, covenant, condition or agreement under this Lease (other than
non-payment of Rent and Additional Charges, an assignment or subletting in
violation of Article 17 or Tenant's abandonment of the Premises) within twenty
(20) days after Landlord's notice to Tenant or, if the failure is of a nature
requiring more than 20 days to cure, then such additional period after the
expiration of such 20-day period as is necessary to effectuate cure in fact, but
only if Tenant commences cure within such 20-day period and thereafter
diligently pursues such cure to completion as soon as possible after the
expiration of such 20-day period, using reasonable good faith efforts and all
due diligence to effectuate cure.


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                       c.  Assignment or Subletting. For an assignment or
sublease made in contravention of any other provisions of Article 17 above,
within twenty (20) days after Landlord's notice to Tenant.

                       d.  No Cure Period. No cure period shall apply for any
other event of default specified in Section 20.1.

                 20.3. Remedies Upon Occurrence of Default. On the occurrence
of a default which Tenant fails to cure after notice and expiration of the time
period for cure, if any, specified in Section 20.2 above, Landlord shall have
the right either (i) to terminate this Lease and recover possession of the
Premises, or (ii) to continue this Lease in effect and enforce all Landlord's
rights and remedies under California Civil Code Section 1951.4 (by which
Landlord may recover Rent and Additional Charges as it becomes due, subject to
Tenant's right to assign pursuant to Article 17). Landlord may, without any
liability to Tenant for loss or damage thereto or loss of use thereof, store any
property of Tenant located in the Premises at Tenant's expense or otherwise
dispose of such property in the manner provided by law. If Landlord does not
terminate this Lease, Tenant shall in addition to continuing to pay all Rent and
Additional Charges when due, also pay Landlord's costs of attempting to relet
the Premises, any repairs and alterations necessary to prepare the Premises for
such reletting, and brokerage commissions and attorneys' fees incurred in
connection therewith, less the rents, if any, actually received from such
reletting. Notwithstanding Landlord's election to continue this Lease in effect,
Landlord may at any time thereafter terminate this Lease pursuant to this
Section 20.3.

                 20.4. Damages Upon Termination. If and when Landlord terminates
this Lease pursuant to Section 20.3, Landlord may



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exercise all its rights and remedies available under California Civil Code
Section 1951.2, including the right to recover from Tenant the worth at the time
of award of the amount by which the unpaid Rent and Additional Charges for the
balance of the Term after the time of award exceeds the amount of such Rent and
Additional Charges loss that the Tenant proves could have been reasonably
avoided. As used herein and in Civil Code Section 1951.2, "time of award" means
either the date upon which Tenant pays to Landlord the amount recoverable by
Landlord, or the date of entry of any determination, order or judgment of any
court or other legally constituted body determining the amount recoverable,
whichever occurs first.

                  20.5. Landlord's Right to Cure Defaults.  If Tenant fails
to pay Rent and Additional Charges (other than Base Rent, Escalation Charges
and/or the Antenna Fee) required to be paid by it hereunder, or fails to perform
any other obligation under this Lease, and Tenant fails to cure such default
within the applicable cure period specified in Section 20.2 above, then Landlord
may, without waiving or releasing Tenant from any of its obligations or such
default, and after first giving notice to Tenant of Landlord's intent to
exercise its rights under this Section 20.5, make any such payment or perform
such other obligation on behalf of Tenant. All payments so made by Landlord, and
all costs and expenses incurred by Landlord to perform such obligations
(together with interest at the Lease Rate on all such payments, costs and
expenses calculated from the date of expenditure thereof until repaid by
Tenant), shall be due and payable by Tenant as Additional Charges within ten
(10) days after receipt of Landlord's demand therefor.

                  20.6. Waiver of Forfeiture. Tenant hereby waives Code of Civil
Procedure Section 1179, Civil Code Section 3275, and all similar


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<PAGE>   168
laws now or hereinafter enacted, which would entitle Tenant to seek relief
against forfeiture in connection with any termination of this Lease under this
Article 20 or otherwise.

                  20.7. Landlord Default; Tenant's Right to Cure Landlord
Default. Landlord shall not be in default in the performance of any of its
obligations under this Lease unless and until Tenant gives notice of such
default to Landlord and any encumbrancer under Article 21 below, the name of
which has been previously furnished to Tenant, and Landlord or such encumbrancer
fails within twenty (20) days after the receipt of Tenant's notice to commence
cure of such default and thereafter use reasonable good faith efforts and all
due diligence to pursue such cure to completion. If Landlord is in default in
the performance of its obligations under this Lease after the expiration of the
notice and cure period specified in the first sentence of this Section 20.7, and
such default is a failure by Landlord to make repairs and/or comply with the
provisions of laws applicable to the Premises in accordance with such
obligations as are imposed on Landlord by this Lease so to do, then Tenant may,
without waiving or releasing Landlord from any of its obligations or such
default, and after first giving Landlord and any encumbrancer notice of Tenant's
intent to invoke its rights under this Section 20.7, perform such obligation on
behalf of Landlord, but only if the performance of such obligation would not
constitute a Limited Alteration if made by Tenant as an Alteration, and such
performance by Tenant does not interfere with the use, occupancy or quiet
enjoyment by other tenants of the Complex. If Landlord is in default in the
performance of its obligations under this Lease after the expiration of the
notice and cure period specified in the first sentence of this Section 20.7, and
such default is a failure by Landlord to provide electricity or



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<PAGE>   169
ventilation or air conditioning to the Premises in accordance with the
applicable standards of Article 8, or such default is a failure by Landlord to
make repairs and/or comply with the provisions of laws applicable to the
Premises in accordance with such obligations as are imposed on Landlord by this
Lease so to do, and Tenant's performance of such obligation would constitute a
Limited Alteration if made by Tenant as an Alteration, and as a result of either
such default Tenant cannot use and occupy the Premises, and is in fact not doing
business in the Premises on account thereof, then Tenant may, without waiving or
releasing Landlord from any of its obligations or such default, and after first
giving Landlord and any encumbrancer notice of Tenant's intent to invoke its
rights under this Section 20.7, perform such obligation on behalf of Landlord.
All costs and expenses incurred by Tenant to perform such obligations (together
with interest at the Lease Rate) on all such costs and expenses calculated from
the date of expenditure thereof until repaid by Landlord), shall be due and
payable by Landlord promptly upon receipt of Tenant's demand therefor, but
Tenant shall have no right to offset any amounts claimed due by Tenant under
this Section 20.7 against Rent and Additional Charges otherwise payable under
this Lease.

                  20.8. Remedies Cumulative. The rights and remedies of the
parties under this Lease are cumulative and in addition to, and not in lieu of,
any other rights and remedies available to each party at law or in equity. A
party's pursuit of any such right or remedy shall not constitute a waiver or
election of remedies with respect to any other right or remedy. The rights and
remedies of Landlord under this Lease for failure of Tenant to pay Rent apply to
any failure of Tenant to pay Additional Charges as if such Additional Charges
constituted Rent under applicable law.



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<PAGE>   170
         21. Subordination, Attornment and Non-disturbance.

                  21.1.  Landlord Right to Encumber; Subordination and
Attornment. Landlord shall have the right, at any time and from time to time, to
place on the Complex, or any part thereof or interest therein, or encumber the
Complex, or any part thereof or interest therein, with one or more ground leases
or underlying leases, mortgages, deeds of trust or any other security
instrument. Upon execution and delivery of an SNDA as hereinafter provided, this
Lease and all of Tenant's rights hereunder shall be subordinate to any such
ground lease or underlying lease, and the lien of any mortgage, deed of trust,
or any other security instrument now or hereafter so affecting or encumbering
the Complex, or any part thereof or interest therein, and to any and all
advances made on the security thereof or Landlord's interest therein, and to all
renewals, modifications, consolidations, replacements and extensions thereof
existing as of the date hereof (an "encumbrance", the holder of the beneficial
interest thereunder being referred to as an "encumbrancer"). An encumbrancer
may, however, subordinate its encumbrance to this Lease, and if an encumbrancer
so elects by notice to Tenant, this Lease shall be deemed prior to such
encumbrance. If any encumbrance to which this Lease is subordinate is
foreclosed, or a deed in lieu of foreclosure is given to the encumbrancer
thereunder, Tenant shall attorn to the purchaser at the foreclosure sale or to
the grantee under the deed in lieu of foreclosure; and if any encumbrance
consisting of a ground lease or underlying lease to which this Lease is
subordinate is terminated, Tenant shall attorn to the lessor thereof.
Subordination of this Lease and Tenant's attornment pursuant to this Section
21.1 shall only be effected by a written and recorded Subordination
Non-Disturbance and Attornment Agreement


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<PAGE>   171
(an "SNDA") containing terms and conditions consistent with the provisions of
this Article 21 and otherwise consistent with then customary industry and
commercially reasonable practices of institutional encumbrancers. The SNDA shall
be executed and acknowledged by Landlord, Tenant and the encumbrancer thereunder
and recorded by Landlord at its cost and expense concurrently with the
encumbrance transaction to which it relates. No SNDA shall enlarge Tenant's
obligations or diminish Tenant's rights under this Lease, including use by
Landlord of insurance proceeds for repair of damage or destruction under Article
12, or use of an award made on a taking to restore the Premises and/or the
Complex under Article 13 above, and the right of Tenant to any award made in a
taking pursuant to Article 13 above. Tenant shall have no obligation to pay any
fees, costs or expenses of an encumbrancer or Landlord with respect to any SNDA
hereunder. Tenant shall execute, acknowledge and deliver in the form reasonably
requested by Landlord or any encumbrancer, any documents required to make this
Lease prior to the lien of any encumbrance, or to evidence such attornment.

                  21.2. Non-disturbance. If any encumbrance to which this Lease
is subordinate is foreclosed, or a deed in lieu of foreclosure is given to the
encumbrancer thereunder, or if any encumbrance consisting of a ground lease or
underlying lease to which this Lease is subordinate is terminated, this Lease
shall not terminate, and the rights and possession of Tenant under this Lease
shall not be disturbed if (i) no default by Tenant then exists under this Lease
beyond the giving of any applicable notice and the expiration of any applicable
cure period; and (ii) Tenant attorns to the purchaser, grantee, or successor
lessor as provided in Section 21.1 above or, if requested, enters into a new
lease for the balance of


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<PAGE>   172
the Term upon the same terms and provisions contained in this Lease. Any
encumbrancer or successor-in-interest to an encumbrancer, as Landlord, shall,
however, not be bound by (A) any payment of Rent and Escalation Charges for more
than one (1) month in advance (other than Premium Rent), (B) any amendment or
modification of this Lease made without the written consent of such
encumbrancer, or (C) any breach of this Lease by any predecessor-in-interest to
such encumbrancer or to the successor-in-interest to such encumbrancer, except
to the extent such breach would constitute a breach by a successor to Landlord
pursuant to Section 22.1 below if not cured by such successor on account of
liabilities and obligations accruing after the transfer to such successor.

                  21.3. No Superior Encumbrances. Landlord warrants and
represents to Tenant that as of the Lease Date, there exists no liens or
encumbrances on the Complex superior to this Lease (other than liens for Real
Estate Taxes), which if enforced or foreclosed would result in the termination
of this Lease.

         22.  Sale or Transfer by Landlord; Lease Non-Recourse.

                  22.1.  Release of Landlord on Transfer.  Landlord may at
any time transfer, in whole or in part, its right, title and interest under this
Lease and in the Complex, or any portion thereof. If the original Landlord
hereunder, or any successor to such original Landlord, transfers (by sale,
assignment or otherwise) its right, title or interest in the Complex, the
original Landlord or such successor shall automatically be released from all
liabilities and obligations of the original Landlord or such successor under
this Lease accruing after such transfer provided such new owner assumes in
writing all such liabilities and obligations accruing after such transfer and
all such liabilities and obligations accruing after such transfer shall in all
events be


                                     -159-
<PAGE>   173
binding upon the new owner. Tenant shall attorn to each such new owner. If in
connection with any transfer effected by the then Landlord hereunder, such
Landlord transfers to the new owner any security provided by Tenant to Landlord
for the performance of any obligation of Tenant under this Lease, then such
Landlord shall be released from any further responsibility or liability for such
security.

                  22.2. Lease Non-recourse to Landlord. Landlord shall never be
personally liable under this Lease, and Tenant shall look solely to (i)
Landlord's interest in the Complex, (ii) the proceeds of any insurance payable
to Landlord on account of damage or destruction to the Complex, or any award
made to Landlord on account of a taking pursuant to Article 13 above, and (iii)
cash revenue from the Project paid to Landlord and not then distributed to the
constituent members of Landlord, for recovery of any damages for breach of this
Lease by Landlord or on any judgment in connection therewith, except that
Landlord shall be personally liable under this Lease for any default in its
obligation to make payment of Construction Allowances pursuant to Section 10.4
above, unless Landlord pays the amount of any then unpaid Construction
Allowances into an escrow established with a national banking association
designated by Landlord with instructions to make payment thereof to Tenant in
accordance with the applicable requirements of Section 10.4, but any interest
accruing on such escrowed Construction Allowance funds shall, except in the
event of a dispute between the parties governed by Section 10.4.a, be paid to
Landlord. Such escrow shall be on terms and conditions consistent with the
applicable requirements of Section 10.4 for the disbursement of Construction
Allowances thereunder, and any agreement with, or instructions to, the escrow
holder shall


                                     -160-
<PAGE>   174
specifically provide that Tenant may enforce its rights for disbursement of
Construction Allowances against such escrow holder in accordance with the
applicable provisions of this Lease, except that, if so specified in the
agreement with, or instructions to, such escrow holder, such escrow holder may
commence an action in interpleader with respect to any dispute regarding
disbursement of Construction Allowances, and deposits the amount in dispute with
the court in which such interpleader action is commenced in accordance with
applicable law, then such escrow holder shall be relieved and exonerated from
all further liability with respect to such dispute, and Landlord and Tenant
shall proceed with resolution of such dispute in accordance with the applicable
provisions of this Lease, including arbitration pursuant to Section 31.17,
subject, however, to the conditions thereon set forth in Section 10.4 above.
Payment by Landlord of Construction Allowances into an escrow hereunder shall
not relieve Landlord of its obligations with respect to the disbursement thereof
pursuant to Section 10.4 above, subject, however, to the limitations on personal
liability set forth in this Section 22.2. Except to the extent Landlord is
personally liable under this Section 22.2, none of the persons or entities
comprising or representing Landlord (whether partners, shareholders, officers,
directors, trustees, employees, beneficiaries, agents or otherwise) shall ever
be personally liable under this Lease for any such damages or judgment and
Tenant shall have no right to effect any levy of execution against any assets
(other than their interest in the Complex) of such persons or entities on
account of any such liability or judgment. Any judgment lien obtained by Tenant
for recovery of damages for breach of this Lease by Landlord shall attach to the
Complex in accordance with applicable law, regardless of the then identity of
the Landlord


                                     -161-
<PAGE>   175
under this Lease at the time of attachment, or whether such then Landlord is
liable for such breach by a prior Landlord; any successor Landlord of a prior
Landlord, which prior Landlord has breached this Lease, waives any right to
contest or object to the attachment of any such judgment lien to the Complex on
the basis that such judgment lien is attributable to a breach by such prior
Landlord; if Tenant perfects any judgment lien on the Complex, then from and
after the date such judgment lien attaches to the Complex, Tenant shall have the
right to offset Rent and Additional Charges otherwise payable under this Lease
against the amount of such judgment until such judgment is satisfied in full,
upon which Tenant shall take such measures as are necessary or appropriate in
order to remove such judgment lien from the Complex; and any judgment lien
attaching to the Complex hereunder, and any levy of execution thereon, and any
attachment of proceeds under clauses (ii) or (iii) above, shall be subject and
subordinate to any encumbrance pursuant to Section 21.1 above, and the SNDA
thereunder shall so provide.

         23. Estoppel Certificate.

                  23.1. Tenant's Certificate. On not less than ten (10) days'
prior notice by Landlord, Tenant shall execute, acknowledge, and deliver to
Landlord, certificates as specified by Landlord certifying: (i) that this Lease
is unmodified and in full force and effect (or, if there have been
modifications, that this Lease is in full force and effect, as modified, and
identifying each modification); (ii) each Delivery Date and each Expiration
Date; (iii) that Tenant has accepted the Premises then delivered to Tenant under
this Lease (or the reasons Tenant has not accepted the Premises); (iv) the
amount of the Base Rent and current Escalation Charges, if any, and the date to
which such Rent and Escalation


                                     -162-
<PAGE>   176
Charges has been paid; (v) whether there are any existing defenses against the
enforcement of Tenant's obligations under this Lease; (vi) that no default of
Landlord is claimed by Tenant, except as to any defaults specified in the
certificate; and (vii) such other matters as may be reasonably requested by
Landlord.

                  23.2. Landlord's Certificate. On not less than ten (10) days
prior notice by Tenant that Tenant desires to enter into an assignment or
sublease, or that Tenant requires a certificate hereunder in connection with a
transaction (such as a public offering of shares or a transaction with an
Affiliate) which Tenant desires to undertake, Landlord shall execute,
acknowledge and deliver to Tenant certificates as specified by Tenant,
certifying (i) that this Lease is unmodified and in full force and effect (or,
if there have been modifications, that this Lease is in full force and effect,
as modified, and identifying each modification); (ii) each Delivery Date and
each Expiration Date; (iii) the amount of the Base Rent and current Escalation
Charges, if any, and the date to which such Rent and Escalation Charges has been
paid; (iv) whether there are any existing defenses against the enforcement of
Landlord's obligations under this Lease; (v) that no default of Tenant is
claimed by Landlord, except as to any defaults specified in the certificate; and
(vi) such other matters as may be reasonably requested by Tenant.

                  23.3. Effect of Certificate. Any Tenant certificate may be
relied upon by any prospective purchaser of any part or interest in the Complex
or encumbrancer (as defined in Section 21.1) and, at Landlord's request, Tenant
shall deliver such certificate to any such entity. In addition, at Landlord's
request, Tenant shall, if Tenant is not then a publicly traded entity listed on
a national or regional stock exchange or over the


                                     -163-
<PAGE>   177
counter stock exchange, provide to Landlord for delivery to any such entity such
information as may reasonably be requested by any such entity. Any Landlord
certificate may be relied upon by any prospective transferee of Tenant's
interest under this Lease or sublease of a portion of the Premises, or a third
party to a transaction requiring such certificate pursuant to Section 23.2
above, and at Tenant's request, Landlord shall deliver such certificate to any
such transferee or third party. A party shall not be liable to the requesting
party or third person or entity requesting or receiving a certificate hereunder
on account of any information therein contained, notwithstanding the omission
for any reason to disclose correct and/or relevant information, but such party
shall be estopped with respect to the requesting party or such third person or
entity from asserting any right or obligation or utilizing any defense which
contravenes or is contrary to such information, except that no such certificate
shall waive a party's rights with respect to Escalation Charges, and no party
shall be estopped by such certificate with respect thereto. If a party fails or
refuses to give a certificate hereunder within the time period herein specified,
then the requesting party shall have the right to treat such failure or refusal
as a default by the other party.

         24. No Light, Air, or View Easement. Nothing contained in this Lease
shall be deemed, either expressly or by implication, to create any easement for
light and air or access to any view. Any diminution or shutting off of light,
air or view to or from the Premises by any structure which now exists or which
may hereafter be erected, whether by Landlord or any other person, shall in no
way affect this Lease or Tenant's obligations hereunder, entitle


                                     -164-
<PAGE>   178
Tenant to any reduction of Rent and Additional Charges, or impose any liability
on Landlord.

         25. Holding Over. No holding over by Tenant shall operate to extend the
Term. If Tenant remains in possession of any part of the Premises after
expiration or termination of the Term applicable to such Premises or after the
expiration or termination of this Lease, (i) Tenant shall become a tenant at
sufferance upon all the applicable terms and conditions of this Lease, except
that Base Rent shall be increased to equal 125% of the Base Rent then in effect
for the first thirty (30) days after the applicable expiration or termination,
and thereafter Base Rent shall be increased to equal 200% of the Base Rent then
in effect; (ii) commencing thirty (30) days after the date of such expiration
or termination, Tenant shall indemnify, defend, protect and hold harmless
Landlord from any and all liability, loss, damages, costs or expense (including
loss of rent to Landlord, or additional rent payable by any tenant to whom
Landlord has leased all or part of the Premises, and reasonable attorneys' fees)
suffered or incurred by Landlord resulting from Tenant's failure timely to
vacate the Premises; and (iii) such holding over by Tenant shall constitute a
default by Tenant. Landlord's acceptance of Rent and/or Additional Charges if
and after Tenant holds over shall not convert Tenant's tenancy at sufferance to
any other form of tenancy or result in a renewal or extension of the Term of
this Lease.

         26. Waiver. Failure of a party to declare a default by the other party
upon occurrence thereof, or delay in taking any action in connection therewith,
shall not waive such default, but a party shall have the right to declare such
default at any time after its occurrence. To be effective, a waiver of any
provision of this Lease, or any default, shall be in writing and signed by the



                                     -165-
<PAGE>   179
waiving party. Any waiver hereunder shall not be deemed a waiver of subsequent
performance of any such provision or subsequent defaults. The subsequent
acceptance of Rent and/or Additional Charges hereunder, or endorsement of any
check by Landlord, shall not be deemed to constitute an accord and satisfaction
or a waiver of any preceding default by Tenant, except as to the particular Rent
and/or Additional Charges so accepted, regardless of Landlord's knowledge of the
preceding default at the time of acceptance of the Rent and/or Additional
Charges. No course of conduct between Landlord and Tenant, and no acceptance of
the keys to or possession of the Premises by Landlord before an applicable
Expiration Date shall constitute a waiver of any provision of this Lease or of
any default, or operate as a surrender of this Lease.

         27. Notices. All notices, approvals, consents, demands and other
communications from one party to the other given pursuant to this Lease shall be
in writing and shall be made by hand delivery, by use of a nationally recognized
overnight courier service, such as Federal Express or Airborne Express, or by
deposit in the United States mail, certified, registered or Express, postage
prepaid and return receipt requested. Notices shall be addressed if to Landlord,
to Landlord's Address, and if to Tenant, to Tenant's Address. Landlord and
Tenant may each change their respective Addresses from time to time by giving
written notice to the other of such change in accordance with the terms of this
Article 27, at least ten (10) days before such change is to be effected. Any
notice given in accordance with this Article 27 shall be deemed to have been
given (i) on the date of hand delivery if sent by hand delivery or (ii) on the
earlier of the date of delivery or attempted delivery (as shown by the return
receipt or other delivery record) if sent by courier service or mailed.


                                     -166-
<PAGE>   180
         28.  Authority; Tenant Financial Information; Confidentiality.

                  28.1.  Authority.  Each party, and each of the persons
executing this Lease on behalf of each party, represent and warrant that (i)
such party is a duly formed, authorized and existing corporation, partnership or
trust (as the case may be), (ii) such party is qualified to do business in
California, (iii) such party has the full right and authority to enter into this
Lease and to perform all of such party's obligations hereunder, and (iv) each
person signing on behalf of such party is authorized to do so. Each party shall
deliver to the other party, upon the other party's request, such certificates or
resolutions authorizing such party's execution and delivery of this Lease.

                  28.2. Tenant Financial Information; Confidentiality. If Tenant
is not then a publicly traded entity listed on a national or regional stock
exchange or over the counter stock exchange, Tenant shall deliver to Landlord,
within twenty (20) days after receipt of a written request from Landlord,
audited financial statements for Tenant issued not more than fifteen (15) months
prior to Landlord's request, and such other financial information regarding
Tenant, and its constituent members, as reasonably requested by Landlord.
Landlord shall utilize such financial information solely for the purpose of
evaluating Tenant's then credit standing in relationship to its obligations
under this Lease. Such financial information (and all additional financial
information derived therefrom) shall be held confidential by Landlord as a trade
or business secret, and Landlord shall impose by written agreement in the form
attached hereon as Exhibit F-2, such confidentiality requirement on any employee
or third person to whom Landlord delivers or discloses such financial
information. Landlord may, however, disclose such financial information (i) to
the extent required by any applicable



                                     -167-
<PAGE>   181
governmental law, ordinance, rule or regulation, (ii) in any litigation or
proceeding between the parties with respect to any dispute between them
regarding this Lease (subject to such protective orders to prevent disclosure
and protect the confidentiality of such financial information as may be
available under applicable law, to which Landlord hereby consents and Landlord
shall not oppose), (iii) to the extent required by judicial process (such as a
subpoena duces tecum), after notice by Landlord to Tenant of the receipt of such
judicial process, and subject to Tenant's right to seek such protective orders
to prevent disclosure and protect the confidentiality of such financial
information as may be available in accordance with applicable law (to which
Landlord hereby consents and shall not oppose); (iv) if such financial
information is generally known to the public or is in the public domain, other
than on account of a breach by Landlord of its obligations under this Section
28.2, (v) to Landlord's executives, accountants, attorneys, and other agents and
representatives, subject however to the imposition on such executives,
accountants, attorneys and other agents and representatives by written agreement
in the form attached hereto as Exhibit F-2 of the confidentiality of this
Article 28, or (iv) to perspective transferees (subject however to the
impositions on such transferees of the written agreement in the form attached
hereto as Exhibit F-2 to impose the confidentiality requirements of this Article
28).

         29. Parking. Landlord shall make available during the Term for the use
by Tenant, and its officers and employees, one (1) automobile valet parking
space for each 6,250 feet of Rentable Area contained in the Premises on the
lower level of the Building parking garage, and five (5) self-park center aisle
parking spaces


                                     -168-
<PAGE>   182
on the service level of the Building parking garage, to be parked in tandem (or
such additional service level parking spaces as may, after the Lease Date,
become available, up to a total of fourteen [14] such spaces) such parking to be
available with full in and out privileges. In addition, if so requested by
Tenant, Landlord shall make available to Tenant on a terminable month-to-month
basis during the Term, to the extent then available, the number of additional
parking spaces in the Building parking garage so requested by Tenant. If the
total parking area or total number of spaces allocable to Building tenants in
the Building parking garage is required by law, ordinance, rule or regulation to
be reduced, the number of parking spaces for which parking is then made
available to Tenant shall be reduced in an amount proportionate to the reduction
in the total parking area in the Building parking garage. Tenant shall pay
Landlord for the parking spaces provided pursuant to this Section 29 at the
Building standard monthly (or longer term if available) parking rate or the
parking garage operator's standard monthly rate as adjusted and charged on a
non-discriminatory basis from time to time. Tenant's use of all other parking
spaces not allocated to Tenant hereunder shall be subject to availability. In
addition, if Tenant notifies Landlord that Tenant does not require all or any of
such allocated parking spaces, Landlord may thereafter rent such spaces not
required by Tenant to any other party. Tenant shall pay Landlord, or the parking
garage operator, for all parking spaces at the times and in the manner required
by Landlord or such parking garage operator with respect to the operation of the
Building parking garage.

         30. Signage. Subject to any right of Pacific Telesis (another tenant of
the Building) to review and approve such signage, Landlord shall (i) provide
Tenant with signage in the


                                     -169-
<PAGE>   183
lowrise elevator bank serving Floors 2 - 14 of the Building at the location and
of the design set forth in Exhibit J hereto if Tenant and its Affiliates then
physically occupy at least ten (10) Floors served by the lowrise elevator bank,
and (ii) provide Tenant with signage in the midrise elevator bank serving Floors
15 - 25 of the Building at the location and of the design set forth in Exhibit J
hereto if Tenant and its Affiliates then physically occupy at least nine (9)
Floors served by the midrise elevator bank. Tenant's signage in the lowrise
elevator bank and/or midrise elevator bank shall be non-exclusive to Tenant,
unless and so long as Tenant physically occupies all Floors served by the
lowrise elevator bank and/or midrise elevator bank, in which event with respect
to such elevator bank, Tenant's signage shall be exclusive, and no other tenant
or occupant of the Building shall have the right to place signage in such
elevator bank. If, at any time, Tenant or its Affiliates do not physically
occupy the required number of Floors in the lowrise and/or midrise of the
Building, then Tenant's signage rights hereunder shall be suspended (subject to
reinstatement if Tenant thereafter meets such requirements, but also subject to
any signage rights then reposing in any other tenant of the Complex), and
Landlord shall have the right at Tenant's cost and expense to remove Tenant's
signage or cause Tenant to effect such removal at Tenant's cost and expense.
Landlord shall install Tenant's sign hereunder at Tenant's cost and expense.
Tenant shall, however, be responsible for obtaining all necessary permits and
approvals from governmental authorities having jurisdiction for the design,
installation and maintenance of Tenant's sign hereunder. Tenant shall be
responsible for maintaining its sign hereunder unless otherwise elected by
Landlord, in which event Landlord shall maintain Tenant's sign at


                                     -170-
<PAGE>   184
Tenant's cost and expense. Tenant shall reimburse Landlord for all costs and
expenses due from Tenant hereunder within thirty (30) days after receipt of
Landlord's invoice for such costs and expenses. For purposes of this Article 30,
Tenant may meet the requirement for physical occupancy of Floors both under this
Lease and under subleases with other tenants of the Building or by assignment of
leases of other tenants of the Building, as of the time in question. Tenant's
signage rights under this Article 30 are personal to the signatory Tenant of
this Lease, Charles Schwab & Co., Inc., and such Tenant's Affiliates, and may
not be assigned or transferred in any manner, including pursuant to Article 17,
except in connection with an assignment or sublease under Article 17 to an
Affiliate of such Tenant.

         31.  Miscellaneous.

                  31.1.  No Joint Venture.  This Lease does not create any
partnership or joint venture or similar relationship between
Landlord and Tenant.

                  31.2. Successors and Assigns. Subject to the provisions of
Article 17 regarding assignment, all of the provisions, terms, covenants and
conditions contained in this Lease shall bind, and inure to the benefit of, the
parties and their respective successors and assigns.

                  31.3. Construction and Interpretation. The words "Landlord"
and "Tenant" include the plural as well as the singular. If there is more than
one person comprising Tenant or Landlord, the obligations under this Lease
imposed on Tenant or Landlord, as the case may be, are joint and several.
References to a party or parties refers to Landlord or Tenant, or both, as the
context may require. The captions preceding the Articles, Sections and
subsections of this Lease are inserted solely for convenience of


                                     -171-
<PAGE>   185
reference and shall have no effect upon, and shall be disregarded in connection
with, the construction and interpretation of this Lease. Use in this Lease of
the words "including", "such as", or words of similar import when following a
general matter, shall not be construed to limit such matter to the enumerated
items or matters whether or not language of non-limitation (such as "without
limitation") is used with reference thereto. All provisions of this Lease have
been negotiated at arm's length between the parties and after advice by counsel
and other representatives chosen by each party and the parties are fully
informed with respect thereto. Therefore, this Lease shall not be construed for
or against either party by reason of the authorship or alleged authorship of any
provision hereof, or by reason of the status of the parties as Landlord or
Tenant, and the provisions of this Lease and the Exhibits hereto shall be
construed as a whole according to their common meaning in order to effectuate
the intent of the parties under the terms of this Lease.

                  31.4. Severability. If any provision of this Lease, or the
application thereof to any person or circumstance, is determined to be illegal,
invalid or unenforceable, the remainder of this Lease, or its application to
persons or circumstances other than those as to which it is illegal, invalid or
unenforceable, shall not be affected thereby and shall remain in full force and
effect, unless enforcement of this Lease as so invalidated would be unreasonable
or grossly inequitable under the circumstances, or would frustrate the purposes
of this Lease.

                  31.5. Entire Agreement; Amendments. This Lease, together with
the Exhibits hereto, contain all the representations and the entire agreement
between the parties with respect to the subject matter hereof and any prior
negotiations, correspondence,


                                     -172-
<PAGE>   186
memoranda, agreements, representations or warranties are replaced in total by
this Lease, and the Exhibits hereto. Neither Landlord nor Landlord's agents have
made any warranties or representations with respect to the Premises or any other
portion of the Complex, except as expressly set forth in this Lease and the
Exhibits hereto. This Lease may be modified or amended only by an agreement in
writing signed by both parties.

                  31.6.  Governing Law.  This Lease shall be governed by
and construed pursuant to the laws of the State of California.

                  31.7. Litigation Expenses. If either party brings any action
or proceeding against the other (including any cross-complaint, counterclaim or
third party claim) to enforce or interpret this Lease or otherwise arising out
of this Lease, the prevailing party in such action or proceeding shall be
entitled to its costs and expenses of suit and enforcing the judgment awarded to
it, including reasonable attorneys' fees.

                  31.8. Standards of Performance and Approvals. Unless otherwise
provided in this Lease, (i) each party shall act in a reasonable manner in
exercising or undertaking its rights, duties and obligations under this Lease
and (ii) whenever approval, consent or satisfaction (collectively, an
"approval") is required of a party pursuant to this Lease or an Exhibit hereto,
such approval shall not be unreasonably withheld or delayed. Unless provision is
made for a specific time period, approval (or disapproval) shall be given within
thirty (30) days after receipt of the request for approval. Nothing contained in
this Lease shall, however, limit the right of a party to act or exercise its
business judgment in a subjective manner with respect to any matter as to which
it has been (A) specifically granted such right, or (B) granted the right to act
in its sole discretion or sole


                                     -173-
<PAGE>   187
judgment, whether "objectively" reasonable under the circumstances and any such
exercise shall not be deemed inconsistent with any covenant of good faith and
fair dealing implied by law to be part of this Lease. The parties have set forth
in this Lease their entire understanding with respect to the terms, covenants,
conditions and standards pursuant to which their obligations are to be judged
and their performance measured, including the provisions of Article 17 with
respect to assignments and sublettings. Whenever a party is required under this
Lease not to unreasonably withhold its approval as to any matter, then any
dispute between the parties regarding whether withholding such approval is
reasonable or unreasonable under the circumstances shall be resolved by
arbitration pursuant to Section 31.17 below.

                  31.9. Brokers. Landlord shall pay to Landlord's Broker and
Tenant's Broker a commission in connection with such Brokers' negotiation of
this Lease pursuant to a separate agreement or agreements between Landlord and
such Brokers. Other than such Brokers, Landlord and Tenant each represent and
warrant to the other that, to such party's knowledge, no broker, agent, or
finder has procured or was involved in the negotiation of this Lease and no such
broker, agent or finder is or may be entitled to a commission or compensation in
connection with this Lease. Landlord and Tenant shall each indemnify, defend,
protect and hold the other harmless from and against any and all liability,
loss, damage, claims, costs and expenses (including reasonable attorneys' fees)
resulting from a claim for a commission or compensation by reason of a broker,
agent or finder asserting that such broker, agent or finder is a procuring cause
for this Lease transaction as a result of having dealt with the indemnifying
party.


                                     -174-
<PAGE>   188
                  31.10. Memorandum of Lease. Each party shall, upon request of
either party, execute, acknowledge and deliver a short form memorandum of this
Lease (and any amendment hereto) in form suitable for recording, and such
memorandum shall be recorded by the requesting party in the Official Records of
the City and County of San Francisco, California, at the requesting party's
expense. In no event shall this Lease be recorded by Tenant.

                  31.11. Quiet Enjoyment. Upon paying the Rent and Additional
Charges and performing all its obligations under this Lease, Tenant may
peacefully and quietly enjoy the Premises during the Term as against all persons
or entities claiming by or through Landlord, subject, however, to the provisions
of this Lease and any encumbrances as specified in Article 21.

                  31.12. Surrender of Premises. Upon the Expiration Date or
earlier termination of this Lease, Tenant shall quietly and peacefully surrender
the Premises to Landlord in the condition specified in Article 9 above and all
other applicable provisions of this Lease (including removal of Alterations
required to be removed under Article 10 above), and shall deliver to Landlord
any keys to the Premises, or any other portion of the Complex, and provide to
Landlord the combination or code of locks on all safes, cabinets, vaults and
security system that will remain in the Premises after the Expiration Date or
earlier termination of this Lease. On or before the Expiration Date or earlier
termination of this Lease, Tenant shall remove all of its personal property from
the Premises and repair at its cost and expense all damage to the Premises or
Complex caused by such removal. All personal property of Tenant not removed
hereunder shall be deemed, at Landlord's option, to be abandoned by Tenant and
Landlord may, without any liability to Tenant for loss or damage thereto or loss
of use thereof, store


                                     -175-
<PAGE>   189
such property in Tenant's name at Tenant's expense to the extent required by
law, and if not so required, dispose of the same in any manner permitted by law.

                  31.13. Building Directory. Landlord shall reserve on the
Building directory, or in any computerized Building directory, up to the number
of Building Directory Spaces specified on the Basic Lease Information for
purposes of identifying Tenant's name, divisions and/or principal employees. As
Floors in the Premises are delivered to Tenant under this Lease, the parties
shall enter into a memorandum reflecting the number of Building Directory Spaces
allocated to such Floor. All costs for the initial strip or inputting of names
shall be borne by Landlord and all reasonable costs for replacement of such
strips or inputting shall be borne by Tenant.

                  31.14. Name of Building; Address. Tenant shall not use the
name of the Building or Complex for any purpose other than as the address of the
business conducted by Tenant in the Premises. Tenant shall, in connection with
all correspondence, mail or deliveries made to or from the Premises, use the
official Building address.

                  31.15.  Exhibits.  The Exhibits specified in the Basic
Lease Information are by this reference made a part hereof.

                  31.16. Arbitration of Fair Market Rent and Fair Market Renewal
Rent. Whenever under this Lease the determination of fair market rent or fair
market renewal rent (hereinafter collectively denominated "fair market rent",
but without affecting the definition of "fair market rent" or "fair market
renewal rent", as the case may be, with respect to the determination to be made
with respect thereto hereunder) is to be made by arbitration, such arbitration
shall be conducted in accordance with this Section


                                     -176-
<PAGE>   190
31.16. The arbitration shall be conducted and determined in the City and County
of San Francisco, solely in accordance with the provisions of this Section
31.16. Within ten (10) days after the parties have exchanged their estimates of
fair market rent under the applicable provisions of this Lease, each party shall
designate an arbitrator to determine fair market rent hereunder. The parties'
arbitrators shall, within ten (10) days after their designation hereunder,
select a third arbitrator. If the parties' arbitrators are unable to agree upon
appointment of such third arbitrator within such 10-day period, then the parties
shall attempt to agree on and appoint such third arbitrator within five (5) days
after the expiration of such 10-day period. If the parties are unable to agree
on such third arbitrator within such 5-day period, then either party, on behalf
of both, may request appointment of such third arbitrator by the then head
official of the San Francisco office of the American Arbitration Association,
and neither party shall raise any objections as to the appointment made by such
official or as to such official's full power and jurisdiction to entertain the
application for and make the appointment. The arbitrators shall be members of
the Appraisal Institute (or its successor organization) with a then current
senior designation of MAI (or then comparable designation) currently certified
under the continuing education program, shall have at least ten (10) years
experience in appraising commercial office properties in the Downtown Financial
District and shall not then be engaged or have been engaged by either Landlord
or Tenant within the prior 5-year period preceding their appointment hereunder.
The arbitrators shall determine which of the two estimates submitted by the
parties pursuant to the applicable provisions of this Lease is closest to the
correct result in the


                                     -177-
<PAGE>   191
arbitrators' opinion. The arbitrators shall have no power to select an
alternative position or a decision different from that proposed by either party.
The decision in which at least two (2) of the arbitrators concur shall be final
and binding upon the parties, absent fraud or gross error. Upon failure, refusal
or inability of an arbitrator to act, his or her successor shall be appointed in
the same manner as provided for original appointment. The party whose position
is not chosen by the arbitrators shall bear the fees and expenses of the
arbitrators. The attorneys' fees and expenses of counsel and consultants to the
respective parties shall be paid by the respective party engaging such counsel
or consultant. The arbitrators shall render their decision in writing, with
counterpart copies to each party, within thirty (30) days after the appointment
of the third arbitrator. The arbitrators shall have no power to modify the
provisions of this Lease.

                  31.17. Arbitration of Dispute. Whenever under this Lease the
determination of a matter or dispute (other than fair market rent) is to be made
by arbitration, such arbitration shall be conducted in accordance with this
Section 31.17 (or by such other alternative dispute resolution mechanism to
which the parties may agree to resolve such dispute), except that a party may
seek prohibitory injunctive relief with respect to any such matter or dispute
which is also subject to arbitration.

                           a. Selection of Arbitrators. By written notice to the
other party, a party shall request a meeting to be attended by the other party
for the purpose of resolving any such matter or dispute. At such meeting, the
parties shall attempt in good faith to resolve the matter or dispute. If the
matter or dispute is not resolved at such meeting, or if the meeting is not
held, either party may, within ten (10) days after the date of (or set for) such


                                     -178-
<PAGE>   192
meeting, make a written request to resolve such dispute by arbitration.

                           b. Selection of Arbitrators. Within ten (10) days
after the date of receipt of such notice, each party shall select an arbitrator.
Such arbitrators shall meet within ten (10) days after selection for the purpose
of resolving the matter or dispute. If, within such 10-day period such
arbitrators are unable to resolve the matter or dispute, then within an
additional 5-day period after the expiration of such 10-day period, they shall
select a third neutral arbitrator. If such arbitrators are unable, within such
5-day period, to appoint the third arbitrator hereunder, the parties shall
jointly appoint such third arbitrator within an additional 5-day period. If the
parties are unable to appoint such third arbitrator within such additional 5-day
period, then either party may request appointment of such third arbitrator the
then head official of the San Francisco office of the American Arbitration
Association, and neither party shall raise any objections as to the appointment
made by such official or as to such official's full power and jurisdiction to
entertain the application for and make the appointment. Upon appointment of a
third arbitrator hereunder, a majority decision shall be final, conclusive and
binding on the parties, at any stage of the proceeding, absent fraud or gross
error. The arbitrators shall resolve the dispute solely in accordance with the
applicable provisions of this Lease with respect to the matter or dispute in
arbitration, and the arbitrators shall have no power to modify any of the
provisions of this Lease. If an arbitrator appointed hereunder dies, resigns,
refuses to act or becomes legally incapacitated, his or her replacement or
successor shall be appointed in like manner specified in this Section 31.17.b.
In any


                                     -179-
<PAGE>   193
arbitration proceeding hereunder, each arbitrator shall have substantial
training and professional experience in the subject matter of the arbitration,
but shall not then be employed or engaged, or have been employed or engaged by a
party for at least five (5) years prior to the arbitration proceeding. The
losing party in the arbitration as determined by the arbitrators shall bear the
costs and expense of all arbitrators. The attorneys' fees and expenses of
counsel and consultants to the respective parties shall be paid by the
respective party engaging such counsel or consultant.

                           c. Decision; Effect of Decision. The arbitrators
shall render their decision in writing and as promptly as possible after the
designation of the last arbitrator, but in no event later than twenty (20) days
after the date of the designation of the last arbitrator. A copy of the decision
of the arbitrators shall be signed by at least a majority of the arbitrators and
given to each party in the manner provided in Article 27 for the giving of
notice. The decision of the arbitrators shall be final, conclusive and binding
on the parties, absent fraud or gross error. The decision of the arbitrators may
be entered as a judgment in a court of competent jurisdiction.

                           d. Procedural Rules. All arbitration under this
Section 31.17 shall be conducted in accordance with the applicable rules of the
American Arbitration Association, to the extent such provisions do not conflict
with the procedures herein set forth. Except as provided in this Section 31.17,
compliance with this Section 31.17 is a condition precedent to the commencement
by a party of judicial proceeding arising out of a matter or dispute which is
subject to arbitration hereunder. All statutes of limitation that would
otherwise be applicable shall



                                     -180-
<PAGE>   194
apply to any arbitration proceeding hereunder. Any attorney-client privilege and
other protections against disclosure of confidential information, including any
protection afforded by the work product privilege for attorneys that could
otherwise be claimed by a party shall be available to and may be claimed by such
party in any arbitration proceeding hereunder. California Code of Civil
Procedure Section 1283.05, and any successor statute, shall apply to any and all
discovery matters in any arbitration proceeding hereunder. Neither party waives
any attorney-client privilege or any other privilege against disclosure of
confidential information by reason of anything contained in or done pursuant to
or in connection with this Section 31.17. All arbitration proceedings hereunder
shall be reported by a certified shorthand court reporter and written
transcripts of such proceedings shall be prepared and made available to the
parties. Any arbitration proceeding hereunder shall be conducted in the City and
County of San Francisco, California.

                  31.18. Survival of Obligations. The indemnity obligations of
the parties under this Lease, and any obligation of a party to make payment of
any sum to the other party or a third person, shall survive the termination or
expiration of this Lease. The provisions of this Section 31.18 govern solely the
obligations between the parties. The provisions of this Lease are for the
exclusive benefit of the parties and not for the benefit of any third person,
and this Lease does not confer any rights, express or implied, upon any such
third person.

                  31.19. Time of the Essence. Time is of the essence of this
Lease and of the performance of each of the provisions contained in this Lease.

                                     -181-
<PAGE>   195
         IN WITNESS WHEREOF, the parties have executed this Lease as of the
Lease Date.

LANDLORD:                                    TENANT:

POST-MONTGOMERY ASSOCIATES,                  CHARLES SCHWAB & CO., INC.
a California general                         a California corporation
partnership

By:  CUSHMAN & WAKEFIELD                     By: /S/ Luis E. Valencia
     OF CALIFORNIA, INC.                         ____________________________ 
     as agent for                                (Signature)
     THE PRUDENTIAL INSURANCE                    Luis E. Valencia
     COMPANY OF AMERICA, a                       ____________________________
     general partner                             (Type or print name)

                                             Its Executive Vice President
By:  /S/ Kennard P. Perry                        ____________________________
     _________________________
     (signature)
                                             By:  /S/ Steven L. Scheid
     Kennard P. Perry                             ___________________________
     _________________________                    (signature)
     (type or print name)
                                                  Steven L. Scheid
Its  Director, Asset Services                     ___________________________
     _________________________                    (type or print name)

By:  UBS ASSET MANAGEMENT (NEW               Its  Executive Vice President
     YORK) INCORPORATED                           and Chief Financial Officer
     as agent for                                 ___________________________
     NLI PROPERTIES WEST, INC.,
     a general partner


     By:  /S/ Joseph B. Dobronyi
          ____________________
          (signature)

          Joseph B. Dobronyi
          ____________________
          (type or print name)


     Its  Vice President, Real Estate
          ____________________



                                     -182-
<PAGE>   196
                           EXHIBIT A-1 THROUGH A-19
                           Floor Plans of Premises


                                   
<PAGE>   197
                                 EXHIBIT A-20

                                 Antenna Area


                                  
<PAGE>   198
                                  EXHIBIT B

                      Landlord's Work for Floors 2 and 3


<PAGE>   199
                                  EXHIBIT C

                           Existing Tenant Options


                                  
<PAGE>   200
                                  EXHIBIT D

                         List of Multi-Tenant Floors


                                  
<PAGE>   201
                                  EXHIBIT E

                 Categories for Escalation Charges Statement


                                 

<PAGE>   202
                             EXHIBIT F-1 and F-2

                          Confidentiality Agreements


<PAGE>   203
                                  EXHIBIT G

                          List of Recorded Documents


<PAGE>   204
                                  EXHIBIT H

                          Janitorial Specifications


<PAGE>   205
                                  EXHIBIT I

                     Rules and Regulations of the Complex


<PAGE>   206
                                  EXHIBIT J

                               Tenant's Signage

Source: OneCLE Business Contracts.