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Exhibit 10(h)

 
                       AMENDMENT DATED NOVEMBER 3, 1997
                                      TO
                         AMENDED EMPLOYMENT AGREEMENT


     Amendment dated November 3, 1997 to the Employment Agreement between
Computervision Corporation (the "Company") and Russell E. Planitzer (the
"Executive") dated as of June 11, 1996 (the "Agreement"), as amended by an
Amendment dated September 22, 1997 (the "Amendment").  All capitalized terms not
defined in this Amendment shall have the meanings set forth in the Employment
Agreement and the Amendment.

     WHEREAS, the Company and the Executive entered into the Amendment with the
purpose of adjusting the exercise price of certain Executive's stock options in
exchange for the release by the Executive of the Company's obligations to pay
the Employee the balance of the Special Bonus due on June 30, 1997 in the amount
of $1,113,500 (the "Special Bonus Payment") and extending the Consultation
Period; and

     WHEREAS, the Company and the Executive desire to amend the Employment
Agreement by rescinding the Amendment and restoring the Company's obligation to
make the Special Bonus Payment;

     NOW, THEREFORE, for valuable consideration, the receipt whereof is hereby
acknowledged, the Company and the Executive agree as follows:

     1.  The Company and the Executive hereby agree to rescind, cancel and
terminate the Amendment, effective immediately.

     2.  From and after the date hereof, the terms and conditions of employment
of the Executive shall be governed solely by the terms and conditions of the
Employment Agreement, as amended hereby as follows:

         (a) The balance of $1,113,500 owed by the Company to the Executive
pursuant to the provisions of Section 4.2 of the Employment Agreement shall bear
interest at the rate of 14% per annum (on the unpaid balance from time to time
outstanding), from July 1, 1997 through the date of payment in full of such
balance. The Company agrees that the Special Bonus shall be paid in full,
together with all accrued and unpaid interest, on the earlier of (i) June 30,
1998 and (ii) the date of consummation of the acquisition of the Company by
Parametric Technology Corporation ("PTC") pursuant to an Agreement and Plan of
Reorganization between the Company and PTC of even date (the "Payment Date").

         (b) Section 2 of the Employment Agreement is hereby amended by
extending the date of expiration of the Consultation Period (as defined therein)
by an additional ten months, from June 30, 1998 to April 30, 1999. During such
additional ten-month period, the Company shall pay the Executive the sum of
$20,000 per
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month, and the Executive agrees to devote up to three (3) days per calendar
month and up to a maximum aggregate of twenty-five (25) days during said 10-
month period to the performance of consulting services to or for the benefit of
the Company.

     2.  The Executive hereby agrees to amend the Adjusted Options (as defined
in the Amendment) so as to increase the applicable option exercise prices to the
respective levels that were in effect prior to the Amendment.

     3.  Except as expressly amended hereby, the Employment Agreement shall
continue to remain in full force and effect.

     IN WITNESS WHEREOF, the parties have caused this Amendment to be executed
as of the date first above written.

                              COMPUTERVISION CORPORATION


                              BY:___________________________________


                              ______________________________________
                              RUSSELL E. PLANITZER

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