FIRST AMENDMENT TO LEASE

This first amendment to lease ("Amendment") is made this 26 day of July, 2001
("Effective Date") by and between SOBRATO INTERESTS II, a California limited
partnership having an address at 10600 N. De Anza Blvd., Suite 200, Cupertino,
California 95014 ("Landlord") and ENTRUST, INC., a Maryland corporation (as
successor in interest to Entrust Technologies) having its principal place of
business at 4975 Preston Park Blvd., Suite 400, Plano, Texas 75093, ("Tenant").

                                   WITNESSETH

WHEREAS Landlord and Tenant entered into a lease dated November 14, 2000, (the
"Lease") for the premises ("Premises") located at 455 El Camino Real, Santa
Clara, California; and

WHEREAS Landlord and Tenant wish to document the Commencement Date, acknowledge
payments made to date by Tenant and provide for the moisture protection of the
floor slabs by Landlord;

NOW THEREFORE, in order to effect the intent of the parties as set forth above
and for good and valuable consideration exchanged between the parties, the Lease
is amended as of the Effective Date as follows:

1.    The Commencement Date is agreed by the Parties to be May 15, 2001.

2.    Landlord acknowledges receipt of the Base Monthly Rent for May and June.
      The portion of the rent received for the period in May prior to the
      Commencement Date shall be credited by Landlord against the rent due for
      July. No late charge shall be assessed by Landlord due to the delayed
      payment of the June rent.

3.    Landlord, at Landlord's expense, has agreed to seal the floor slabs of the
      second and third floors against moisture vapor emission, which work was
      begun on June 27, 2001, and shall be completed within approximately two
      (2) weeks.

4.       The Parties acknowledge that, subject to Landlord's termination right,
         the terms of Section 17 of the Lease allow Tenant to sublease the
         Building for a term in excess of three (3) years.

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5.   Except as hereby amended, the Lease and all of the terms, covenants and
     conditions thereof shall remain unmodified and in full force and effect.

In the event of any conflict or inconsistency between the terms and provisions
of this Amendment and the terms and provisions of the Lease, the terms and
provisions of this Amendment shall prevail.

      IN WITNESS WHEREOF, the parties hereto have set their hands to this
Amendment as of the day and date first above written.

Landlord:                                   Tenant:
SOBRATO INTERESTS III                       ENTRUST, INC.
a California limited partnership            a Maryland Corporation


By: /s/ John Michael Sobrato                By: /s/ J. D. Kendry
   -------------------------------             ------------------------------

Its: General Partner                        Its: VP & CLO
                                                -----------------------------

Source: OneCLE Business Contracts.