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                                  UNITED STATES
                       SECURITIES AND EXCHANGE COMMISSION
                             WASHINGTON, D.C. 20549

                                    FORM 10-Q/A


(Mark one)

  X  Quarterly report pursuant to Section 13 or 15(d) of the Securities Exchange
 --- Act of 1934

                  FOR THE THREE MONTHS ENDED SEPTEMBER 30, 1996

                                       OR

     Transition report pursuant to Section 13 or 15(d) of the Securities 
 --- Exchange Act of 1934


                         COMMISSION FILE NUMBER: 0-27696

                               GENSYM CORPORATION
             (Exact name of registrant as specified in its charter)

           DELAWARE                                              04-2932756
(State or other jurisdiction of                               (I.R.S. Employer
 incorporation or organization)                              Identification No.)

                             125 CAMBRIDGEPARK DRIVE
                               CAMBRIDGE, MA 02140
                    (Address of principal executive offices)

                         TELEPHONE NUMBER (617) 547-2500
              (Registrant's telephone number, including area code)


     Indicate by check mark whether the registrant (1) has filed all reports
required to be filed by Section 13 or 15(d) of the Securities Exchange Act of
1934 during the preceding 12 months (or for such shorter period that the
registrant was required to file such reports), and (2) has been subject to such
filing requirements for the past 90 days:

                    Yes  X                            No 
                        ---                              ---

     As of November 6, 1996 there were 6,153,247 shares of the Registrant's
Common Stock outstanding.

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The purpose of this filing is to include Exhibit 10.1, which was inadvertantly
left off the filing of the Form 10-Q, which was filed on November 13, 1996. 
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                                   SIGNATURES


Pursuant to the requirements of the Securities and Exchange Act of 1934, the
registrant has duly caused this report to be signed on its behalf by the
undersigned thereunto duly authorized.



                                             GENSYM CORPORATION
                                             (Registrant)



                                             /s/ Lowell B. Hawkinson
                                             -----------------------
       Dated: November 14, 1996              Lowell B. Hawkinson
                                             Chief Executive Officer
                                             (Principal Executive Officer)


                                             /s/ Stephen Gregorio
                                             --------------------
       Dated: November 14, 1996              Stephen Gregorio
                                             Vice President Finance and 
                                             Administration,
                                             Chief Financial Officer
                                             (Principal Financial and Accounting
                                             Officer)


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                                Exhibit Index


            Exhibit 10.1 - Amendment to Business Loan Agreement dated 
             October 17, 1996 between Gensym Corporation and State Street 
             Bank and Trust