SECURITIES AND EXCHANGE COMMISSION
                             WASHINGTON, D.C. 20549
                                     -------

                                    FORM 8-K

                                 CURRENT REPORT
                     PURSUANT TO SECTION 13 OR 15(d) OF THE
                         SECURITIES EXCHANGE ACT OF 1934

       Date of report (Date of earliest event reported): November 11, 2002

                              Repligen Corporation
             (Exact Name of Registrant as Specified in its Charter)

           DELAWARE                    0-14656                    04-2729386
- ----------------------------         -----------              ----------------
(State or Other Jurisdiction         (Commission              (I.R.S. Employer
       of Incorporation)             File Number)            Identification No.)

          41 Seyon Street
       Building #1, Suite 100
       Waltham, Massachusetts                                     02453
       ----------------------                                     -----
(Address of principal executive offices)                        (Zip Code)

       Registrant's telephone number, including area code: (781) 250-0111

                           No change since last report
          (Former Name or Former Address, if Changed Since Last Report)



Item 5. Other Events.

Court Rulings on CTLA4 Correction of Inventorship Suit: Court Sets Initial Trial
Date

Repligen is the exclusive licensee of all CTLA4 patent rights owned by the
University of Michigan (the "University"). Repligen and the University believe
that the University has a rightful claim to ownership of certain CTLA4 related
patents of Bristol-Myers Squibb ("Bristol"). Repligen and the University filed a
complaint against Bristol in the United States District Court for the Eastern
District of Michigan in August 2000 seeking a correction of inventorship. The
suit asserts that a scientist from the University made inventive contributions
as part of a collaboration with Bristol scientists and is a rightful inventor on
the patents issued to Bristol. Bristol subsequently filed patents claiming uses
and compositions of CTLA4 naming only Bristol scientists as inventors.

Both Repligen/University and Bristol filed motions for summary judgment in March
2002. Repligen/University's motion requested an affirmative summary judgment for
Repligen/University's claims and Bristol's motion requested dismissal of the
complaint. A hearing on these motions was held on May 23, 2002. On October 17,
2002 the judge denied both motions for summary judgment. On October 31, 2002
Bristol filed a motion for reconsideration of the court's order denying its
motion for summary judgment. On November 7, 2002 the court denied Bristol's
motion for reconsideration. The court has scheduled the trial for April 2003.

A correction of inventorship would result in the University/Repligen having
rights to some or all of Bristol's patents on CTLA4-Ig. Repligen would then have
rights to such technology pursuant to a 2000 License Agreement with the
University, a 1995 Asset Acquisition Agreement with Genetics Institute and other
related agreements. Repligen's failure to obtain ownership rights in the Bristol
patents may restrict Repligen's ability to commercialize CTLA4-Ig. Repligen and
the University have also filed patents related to compositions of matter and
methods of use of CTLA4-Ig. In September 2002, Repligen was issued a U.S. patent
covering the composition of the CTLA4-Ig product form that it is developing.

Item 7.  Financial Statements, Pro Forma Financial Information and Exhibits.

         (a) Financial Statements of Business Acquired: None required.

         (b) Pro Forma Financial Information: None required.

         (c) Exhibits:

             None


                                      - 2 -


                                    SIGNATURE

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

                                      REPLIGEN CORPORATION

                                      By: /s/ Walter C. Herlihy
                                          -------------------------------------
                                          Walter C. Herlihy
                                          Chief Executive Officer and President

Date: November 12, 2002