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                            SIXTH AMENDMENT TO LEASE

This Sixth Amendment to Lease (this "Amendment") is entered into on November 18,
1999, by and between Merit Albuquerque Limited Partnership (hereinafter called
"Landlord"), successor in interest to AIRPARK ASSOCIATES and MUSE Technologies
Corporation (hereinafter called "Tenant");

                                   WITNESSETH

WHEREAS, the Landlord and Tenant entered into that certain Office Lease dated
September 6, 1995 with Amendment dates of January 4, 1996, April 12, 1996,
October 11, 1996, August 14, 1997 and March 8, 1998 covering certain premises
comprising 8,787 rentable square feet (collectively known as the "Lease") in the
office building (the "Building") known as NZ Commercial Center, located at 1601
Randolph SE, Albuquerque, New Mexico, such Premises being more particularly
described in the Lease; and

WHEREAS, Landlord and Tenant are desirous of modifying and amending certain
parts of the Lease;

NOW THEREFORE, in consideration of the mutual promises and obligations contained
herein, the adequacy and sufficiency of which is hereby acknowledged, it is
agreed by and between the parties that the Lease shall be hereby amended in the
following manner and upon the terms and conditions hereinafter set forth:

         1. Expansion of Premises. The Premises shall be expanded to 17,549
            rentable square feet effective December 1, 1999 by the addition of
            8,762 rentable square feet (the "Expanded Premises") as shown on
            Exhibit A and Exhibit A- 1.

         2. Extension of Term. The Lease Term is hereby modified from expiring
            on November 30, 2000 (the "Prior Termination Date") to expiring on
            January 31, 2001 ("Extended Termination Date"). The portion of the
            Lease Term commencing the day immediately following the Prior
            Termination Date ("Extension Date") and ending on the Extended
            Termination Date shall be referred to herein as the "Extended Term".

         3. Base Rent. Beginning December 1, 1999, Base Rent Rental Payments for
            the Leased Premises shall be payable monthly in advance on the first
            day of each month during the Extended Term in the amount of
            $17,579.13.

         4. Improvement Allowance. Landlord agrees to provide $8,000.00 (the
            "Allowance") for improvements to the existing and/or expanded
            Premises.

         5. Sublease. Landlord hereby grants permission for Tenant to sublease
            approximately 673 rentable square feet as shown on Exhibit A-1 to
            MUSE Federal Systems.

Except as provided herein, all other terms, conditions, and covenants under said
Lease shall remain in full force and effect and cannot be modified unless said
modification is reduced to writing and signed by all parties.

Landlord:                                    Tenant:
Merit Albuquerque Limited Partnership        MUSE Technologies Corporation

By:/s/ E. P. Zinman                          By:/s/ Curtiz Gangi
Name: E. P. Zinman                           Name: Curtiz Gangi
Title: General Manager                       Title: President