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Exhibit 10(c)

 
                  AMENDMENT OF MANAGEMENT RETENTION AGREEMENT

COMPUTERVISION CORPORATION (the "Company"), and KATHLEEN A. COTE ("Executive")
agree to enter into this AMENDMENT OF MANAGEMENT RETENTION AGREEMENT dated as of
the 3/rd/ day of November, 1997 as follows:

1.  AMENDMENT OF MANAGEMENT RETENTION AGREEMENT.

The parties originally entered into a Management Retention Agreement dated as of
September 4, 1997 (the "Retention Agreement").  The parties have agreed to
certain modifications of the Retention Agreement as set forth herein (the
"Amendment").

2.  LIMITATION ON COMPENSATION.

Notwithstanding Section 4 of the Retention Agreement, if any portion of the
compensation under the Retention Agreement, or under any other agreement with or
plan of the Company (in the aggregate "Total Payments") would constitute an
"excess parachute payment" under Section 280G of the Internal Revenue Code (the
"Code") then the payments to be made to Executive under the Retention Agreement
shall be reduced such that the value of the aggregate Total Payments that
Executive is entitled to receive shall be one dollar ($1) less than the maximum
amount which Executive may receive without becoming subject to the tax imposed
by Section 4999 of the Code, or which the Company or Kezar may pay without loss
of deduction under Section 280G of the Code. The calculation of such potential
excise tax liability, as well as the method in which the compensation reduction
is applied, shall be conducted and determined by Kezar's independent accountants
whose determinations shall be binding on all parties.

3.   DATE OF TERMINATION

The parties agree that Executive's employment will terminate on May 1, 1998
unless sooner terminated because of Executive's death, by the Company for
"Disability" or "Cause", or by Executive other than for "Good Reason", in
accordance with Section 3 of the Retention Agreement.  From February 1, 1998
through May 1, 1998, Executive shall devote 50 per cent of her time to her
employment, and her compensation shall be $25,000 per month, which is one half
of her regular base pay rate of $600,000 per year.

4.   CONSULTING AGREEMENT.

The parties agree that if Executive's employment with the Company terminates
under conditions entitling her to benefits under Section 4(c) of the Retention
Agreement, Parametric Technology Corporation ("Parametric") will engage
Executive as a consultant, and Executive hereby agrees to provide consulting
services, upon the terms and conditions set forth in the Consulting Agreement
attached to this Amendment as Exhibit "A" during the period commencing on
Executive's "Date of Termination" (as defined in the Retention Agreement) and
ending on May 1, 1999, unless sooner terminated as set forth therein.

5.   CALCULATION OF COMPENSATION ON TERMINATION
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Section 4(c)(ii)(B) of the Retention Agreement is hereby amended to provide that
the annual incentive bonuses paid or payable to Executive for fiscal years 1995
and 1996 shall be used in calculating the severance amount payable under the
Retention Agreement.

6.   ENTIRE AGREEMENT.

Section 7(f) of the Retention Agreement is hereby amended to read as follows:

     This Agreement and the Exhibits attached hereto set forth the entire
     agreement of the parties hereto in respect of the rights and obligations of
     the parties after the occurrence of a Change of Control and the payment of
     compensation upon termination of employment following a Change in Control.
     This Agreement supersedes all prior agreements, promises, covenants and
     arrangements, whether oral or written, by any officer, employee or
     representative of any party hereto in respect of a Change of Control and
     termination of employment following a Change in Control.

7.   NO OTHER MODIFICATIONS.

Except as specifically modified or superseded by this Amendment, the terms and
conditions of the Retention Agreement shall remain in full force and effect.

8.   COUNTERPARTS.

This Amendment may be executed in any number of counterparts, each of which so
executed shall be deemed to be an original, and such counterparts will together
constitute but one Amendment.

IN WITNESS WHEREOF, the parties hereto have duly executed this Amendment as of
the day and year first above written.

COMPUTERVISION CORPORATION                    PARAMETRIC TECHNOLOGY CORP.     
                                                                              
By: _____________________________             By: ____________________________
                                                                              
Name: ___________________________             Name:  _________________________
                                                                              
Title: __________________________             Title:    ______________________
                                                                              
Date: ___________________________             Date:  _________________________

EXECUTIVE

---------------------------------
Kathleen A. Cote

Date: ___________________________

Address: ________________________

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

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                                                                       EXHIBIT A

                             CONSULTING AGREEMENT

PARAMETRIC TECHNOLOGY CORPORATION (the "Company" or "Parametric"), and KATHLEEN 
A. COTE ("Consultant") agree to enter into this CONSULTING AGREEMENT dated as of
the ________ day of ___________________ as follows:

1.   ENGAGEMENT AND TERM.

The Company hereby agrees to engage Consultant, and Consultant hereby agrees, to
provide consulting services to the Company during the period commencing as of 
the date of the Executive's "Date of Termination" (as defined in the Retention 
Agreement) and ending on May 1, 1999 (the "Consulting Period"), unless sooner 
terminated in accordance with Section 4 below.

2.   CONSULTING SERVICES.

(a)  During the Consulting Period, Consultant shall provide consulting services
     with respect to the transition of customers form Computervision Corp. to
     Parametric and with respect to such other transition matters as the
     Chairman/Chief Executive Officer of Parametric may reasonably request.

(b)  Consultant agrees to be available to provide such consulting services at
     such time or times and at such place or places as are mutually convenient
     to both parties.

(c)  While it is the intent of this Agreement that the mutual convenience of the
     parties be served, it is understood between the parties that during the
     Consulting Period Consultant shall act in the capacity of an independent
     contractor and shall not be subject to the direction, control or
     supervision of the Company with respect to the time spent, or procedures
     followed in the performance of her consulting services hereunder.

3.   COMPENSATION.

(a)  During the Consulting Period, the Company agrees to pay Consultant $120,000
     for all services rendered hereunder. Such compensation shall be payable in
     equal monthly installments of $10,000 each.

(b)  During the Consulting Period, all outstanding stock options granted to
     Consultant by Computervision Corp. will continue to vest and be exercisable
     to the same extent that such options would have vested and become
     exercisable if Consultant had continued in employment until the expiration
     of the Consulting Period. At the expiration of the Consulting Period, the
     right to exercise such options to the extent then exercisable shall
     terminate 90 days after such expiration date
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(c)  Except as otherwise provided in the Management Retention Agreement between
     Consultant and Computervision Corp. (the "Retention Agreement"),
Consultant shall not be eligible either to participate in any employee benefit
plans maintained by the Company (or any of its affiliates) or to receive any
fringe benefits during the Consulting Period.

9.   TERMINATION PRIOR TO END OF CONSULTING PERIOD.

Consultant's services shall be terminated prior to the end of the Consulting 
Period as follows:

(a)  The Consultant's services hereunder shall terminate upon her death or total
     disability. In such event,

     (i)    the Company shall pay Consultant (or her legal representative) a
            lump sum amount equal to the remaining unpaid balance of the
            compensation payable for the Consulting Period, and

     (ii)   any unexercised stock options to the extent then vested shall be 
            exercisable in accordance with their terms.

(b)  The Company may terminate Consultant's services hereunder if
     Computervision's or the Company's obligation to pay the benefits described
     in Section 4(c) of the Retention Agreements ceases as a result of
     Consultant's failure to comply with the requirements set forth in Section
     4(f) of the Retention Agreement. In such event, Consultant shall cease to
     have any right to receive any compensation under this Consulting Agreement
     after the date of such termination and all outstanding stock options shall
     immediately be forfeited any nonexercisable.

5.   MISCELLANEOUS.

(a)  This Consulting Agreement shall be governed by and construed in accordance
     with the laws of the Commonwealth of Massachusetts applicable to agreements
     made and to be performed in that State.

(b)  Notices to either party hereto shall be deemed given to the other when
     given in writing and posted as registered or certified mail of the United
     States Post Office, with sufficient postage affixed thereto and addressed
     to the other party at the address shown below, or to such other address as
     shall be substituted therefor by written notice in the manner hereinabove
     provided.

          To Consultant:

               At the address for Consultant set forth below

          To the Company:

               Carl F. Ockerbloom
               Vice President Human Resources
               Parametric Technology Corporation

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                             128 Technology Drive
                               Waltham, MA 02154

(c)  This Consulting Agreement shall inure to the benefit of and shall be
     binding upon the Company, its successors and assigns and shall be binding
     upon Consultant in accord with its items.

(d)  This Consulting Agreement may be assigned by the Company to any of its 
     subsidiaries or affiliates, without consent of Consultant. This Consulting 
     Agreement shall not be assignable by Consultant.

(e)  This Consulting Agreement constitutes the entire understanding between the
     parties with reference to the subject matter hereof and shall not be
     changed or modified except by a written instrument executed by both
     parties.

(f)  The waiver by either party of a breach of any provision of this Consulting 
     Agreement by the other party shall not be construed as a waiver of any 
     subsequent or other breach by such other party.

(g)  Section headings are used herein for convenience of reference only and 
     shall not affect the meaning of any provision of this Consulting Agreement.

IN WITNESS WHEREOF, the parties hereto have duly executed this Consulting 
Agreement as of the day and year first above written.

PARAMETRIC TECHNOLOGY. CORP.           EXECUTIVE

By:__________________________          _________________________________
                                       Kathleen A. Cote

Name:________________________          Date:____________________________

Title:_______________________          Address:_________________________

Date:________________________          _________________________________

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