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                       SECURITIES AND EXCHANGE COMMISSION
                              WASHINGTON, DC 20549
                        --------------------------------
                                  SCHEDULE TO
                                 (Rule 14d-100)
          TENDER OFFER STATEMENT UNDER SECTION 14(d)(1) OR 13(e)(1) OF
                      THE SECURITIES EXCHANGE ACT OF 1934
                               (Amendment No. 2)

                                  Genset S.A.
                           (Name of Subject Company)
                                  Serono S.A.,
                           Serono France Holding S.A.
                                      and
                                  Serono B.V.
                      (Name of Filing Persons (Offerors))

             Ordinary Shares, nominal value of (euro)3.00 per share
                                      and
   American Depositary Shares evidenced by American Depositary Receipts, each
     American Depositary Share representing one-third of one Ordinary Share
                         (Title of Class of Securities)
                                    37244T104
                     (CUSIP Number of Class of Securities)
                                Nathalie Joannes
                                General Counsel
                                  Serono S.A.
                             15bis Chemin des Mines
                                Case Postale 54
                               CH-1211 Geneva 20
                                  Switzerland
                               011-41-22-739-3113
                                    Copy to:

        Jean-Marie Ambrosi                           William A. Groll
Cleary, Gottlieb, Steen & Hamilton          Cleary, Gottlieb, Steen & Hamilton
      41, Avenue de Friedland             City Place House, 55 Basinghall Street
        75008 Paris, France                  London EC2V 5EH, United Kingdom
       011 33 1 40 74 68 00                        011 44 207 614 2200


                 (Name, Address and Telephone Numbers of Persons
  Authorized to Receive Notices and Communications on Behalf of Filing Persons)
                        ---------------------------------
                            Calculation of Filing Fee
--------------------------------------------------------------------------------
       Transaction Valuation*                          Amount of Filing Fee**
             $34,722,144                                     $3,194.44
--------------------------------------------------------------------------------

*   Estimated solely for purposes of calculating the filing fee in accordance
    with Section 14(g)(3) of the Exchange Act. The Transaction Valuation was
    calculated on the basis of (i) the offer price of (a) Euro 3.25 for each of
    the 6,944,007 ADSs outstanding; (b) Euro 9.75 for each of the 300,352
    ordinary shares held by U.S. holders within the meaning of Rule 14d-1(d)
    under the Exchange Act and the 62,257 ordinary shares that would be issued
    to U.S. holders upon exercise of outstanding options that are, or will
    become, exercisable prior to the expiration of the offer; (c) Euro 102.64
    for each of the 86,695 OCEANEs held by U.S. holders, and (d) Euro 1.00 for
    each of the 9,000 warrants held by U.S. holders issued prior to June 2002
    and Euro 6.50 for each of the 15,000 warrants held by U.S. holders issued
    during June 2002 (which results in an aggregate value offered in this tender
    offer in euro of Euro 35,108,335) and (ii) an exchange rate (using the noon
    buying rate in New York City for cable transfers in euro as certified for
    customs purposes by the Federal Reserve Bank of New York on July 10, 2002)
    of U.S. $0.9890 for one euro. The number of Shares, options to purchase
    Shares, OCEANEs and warrants held by U.S. holders and the number of ADSs is
    based on the most current information provided to the bidder by Genset S.A.
    as of the commencement of this offer, as modified to reflect information
    provided by Genset subsequently about the number of OCEANEs and warrants
    held by U.S. holders.
**  The filing fee, calculated in accordance with Section 14(g)(3) of the
    Securities Exchange Act of 1934, as amended, is $92 for every $1,000,000 of
    the aggregate amount of cash proposed to be offered.
|X| Check the box if any part of the fee is offset as provided by Rule
    0-11(a)(2) and identify the filing with which the offsetting fee was
    previously paid. Identify the previous filing by registration statement
    number, or the Form or Schedule and the date of its filing.


                                       
Amount Previously Paid: $2,326.00         Filing Party: Serono S.A. and Serono France Holding S.A.
Form or Registration No.: Schedule TO     Date Filed: July 16, 2002
Amount Previously Paid: $868.44           Filing Party: Serono S.A., Serono France Holding S.A. and Serono B.V.
Form or Registration No.: Schedule TO,    Date Filed: August 21, 2002
Amendment No. 1

                        --------------------------------
[ ]  Check the box if the filing relates solely to preliminary communications
     made before the commencement of a tender offer.
     Check the appropriate boxes below to designate any transactions to which
     the statement relates:
     [X] third-party tender offer subject  [ ] going-private transaction subject
         to Rule 14d-1.                        to Rule 13e-3.
     [ ] issuer tender offer subject to    [ ] amendment to Schedule 13D under
         Rule 13e-4.                           Rule 13d-2.

Check the following box if the filing is a final amendment reporting the results
of the tender offer: [ ]
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This Amendment No. 2 (this "Amendment") amends and supplements the Schedule TO
filed on July 16, 2002, as previously amended (the "Schedule TO"). All
capitalized terms used in this Amendment and not otherwise defined herein have
the meanings ascribed to such terms in the U.S. Offer to Purchase (previously
filed as Exhibit 99(a)(1) to the Schedule TO).

Item 13. Certain Conditions to the U.S. Offer

The information in the U.S. Offer to Purchase contained in the second bullet
point after the first paragraph of Section 13: "Certain Conditions to the U.S.
Offer" is hereby amended and restated in its entirety to read as follows:

o   "if, at or prior to the expiration date of the Offers, the International
    Offer is withdrawn or terminated in accordance with its terms and French
    law."


                                    SIGNATURE

After due inquiry and to the best of my knowledge and belief, I certify that the
information set forth in this statement is true, complete and correct.

Dated: September 10, 2002

                                           SERONO S.A.


                                                  /s/ Jacques Theurillat
                                           -------------------------------------
                                                        (Signature)

                                                    Jacques Theurillat
                                           -------------------------------------
                                                     (Name and Title)

                                                 Director and Deputy Chief
                                                     Executive Officer
                                           -------------------------------------


                                           SERONO FRANCE HOLDING S.A.


                                                  /s/ Jacques Theurillat
                                           -------------------------------------
                                                        (Signature)

                                                    Jacques Theurillat
                                           -------------------------------------
                                                     (Name and Title)

                                                         Director
                                           -------------------------------------


                                           SERONO B.V.


                                                  /s/ Jacques Theurillat
                                           -------------------------------------
                                                        (Signature)

                                                    Jacques Theurillat
                                           -------------------------------------
                                                     (Name and Title)

                                                         Director
                                           -------------------------------------


                                                    /s/ Paul Wilkinson
                                           -------------------------------------
                                                        (Signature)

                                                      Paul Wilkinson
                                           -------------------------------------
                                                     (Name and Title)

                                                 Authorized Representative
                                           -------------------------------------





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