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

                                    FORM 6-K

                        REPORT OF FOREIGN PRIVATE ISSUER
                      PURSUANT TO RULE 13A-16 OR 15D-16 OF
                       THE SECURITIES EXCHANGE ACT OF 1934

                         For the month of October, 2002.

                                   Serono S.A.
                       ----------------------------------
                               (Registrant's Name)

                            15 bis, Chemin des Mines
                                 Case Postale 54
                                CH-1211 Geneva 20
                                   Switzerland
                       ----------------------------------
                    (Address of Principal Executive Offices)

                                     1-15096
                       ----------------------------------
                              (Commission File No.)

     (Indicate by check mark whether the registrant files or will file annual
reports under cover of Form 20-F or Form 40-F.)

     Form 20-F  X  Form 40-F
              -----         -----

     (Indicate by check mark whether the registrant by furnishing the
information contained in this form is also thereby furnishing the information to
the Commission pursuant to Rule 12g3-2(b) under the Securities Exchange Act of
1934.)

     Yes      No  X
        -----   -----

     (If "Yes" is marked, indicate below the file number assigned to the
registrant in connection with Rule 12g3-2(b): 82-______)



GENSET                                                                    SERONO

Media Release



FOR  IMMEDIATE  RELEASE
-----------------------



                     SERONO TENDER OFFERS FOR GENSET EXPIRE



GENEVA,  SWITZERLAND AND PARIS, FRANCE, OCTOBER 31, 2002 - Serono S.A. (Virt-x :
SEO,  NYSE:  SRA) and Genset S.A. (Nasdaq: GENXY, Euroclear: 5433) announce that
the  subsequent  offering  period in Serono's U.S. and international cash tender
offers  for Genset securities expired today, 31 October, at 12:00 noon, New York
City  time  (18:00,  Paris  time).

The  combined results of the U.S. and the international offers will be announced
on  or  about November 8, 2002, following the announcement by the French Conseil
des  marches financiers ("CMF") of the final results of the international offer.
It  was previously announced on September 23, that at the end of the first offer
period,  Serono  held  85.9%  of  the  capital  and  voting  rights  of  Genset.



                                       ***



These  materials  contain certain statements that are neither reported financial
results  nor  other  historical  information.  Because  these  forward-looking
statements  are  subject  to  risks and uncertainties, actual future results may
differ  materially from those expressed in or implied by the statements. Many of
these  risks  and uncertainties relate to factors that are beyond the companies'
ability  to  control  or  estimate  precisely, such as future market conditions,
currency fluctuations, the behavior of other market participants, the actions of
governmental regulators and other risk factors detailed in Serono's and Genset's
filings with the SEC. Readers are cautioned not to place undue reliance on these
forward-looking  statements,  which  speak only as of the date of this document.
The  companies do not undertake any obligation to publicly release any revisions
to these forward-looking statements to reflect events or circumstances after the
date  of  these  materials.


                                     -more-



ABOUT SERONO
Serono  is  a  global  biotechnology  leader.  The  Company  has six recombinant
products  on  the  market,  Gonal-F(R),  Luveris(R),  Ovidrel(R)/Ovitrelle(R),
Rebif(R),  Serostim(R) and Saizen(R) (Luveris(R) is not approved in the USA). In
addition  to  being  the  world leader in reproductive health, Serono has strong
market  positions  in  neurology,  metabolism and growth. The Company's research
programs  are  focused  on  growing  these  businesses  and  on establishing new
therapeutic  areas. Currently, there are seventeen new molecules in development.

In 2001, Serono achieved worldwide revenues of US$1.38 billion, and a net income
of  US$317  million,  making  it  the third largest biotech company in the world
based  on  revenues.  The Company operates in 45 countries, and its products are
sold  in  over 100 countries. Bearer shares of Serono S.A., the holding company,
are  traded on the virt-x (SEO) and its American Depositary Shares are traded on
the  New  York  Stock  Exchange  (SRA).


ABOUT  GENSET
Genset  is  a  genomics-based  biotechnology  company  focused  on  generating a
pipeline  of  drug targets and drug candidates in the areas of CNS and metabolic
disorders.  Genset  has successfully used its integrated technology platform and
association  studies approach to identify and characterize drug targets and drug
response  markers  in  the fields of CNS, metabolic and other diseases. Building
upon the expertise accumulated in various alliances with pharmaceutical partners
and  its portfolio of genomic patents, Genset discovers and validates novel drug
targets  and  candidates  for its own account. Its teams have already discovered
and  launched  the  development  of a lead protein in the metabolism field named
Famoxin,  and  are  continuing  their  research  with  a view to discovering and
developing  other  drugs.  Genset's news releases are available on the Company's
Web  site  at  http://www.genset.fr.
               ---------------------



FOR MORE INFORMATION, PLEASE CONTACT:

SERONO IN GENEVA, SWITZERLAND:
MEDIA RELATIONS:            INVESTOR RELATIONS:         IMAGE SEPT FRANCE :
Tel:  +41-22-739 36 00      Tel:   +41-22-739 36 01     Tel : + 33 1 53 70 74 68
Fax:  +41-22-739 30 85      Fax:   +41-22-739 30 22     Fax : + 33 1 53 70 74 80
http://www.serono.com       Reuters: SEOZ.VX / SRA.N
---------------------       Bloomberg: SEO VX / SRA US

SERONO, INC., ROCKLAND, MA
MEDIA RELATIONS:
Tel.  +1 781 681 2340
Fax:  +1 781 681 2935
http://www.seronousa.com
------------------------

GENSET                      BURNS MCCLELLAN
+331 55 04 59 00            +1 212 213 0006
Marc Vasseur                Media: Justin Jackson
Chairman & CEO              Investors: Jonathan M. Nugent



   GENSET is listed on the NOUVEAU MARCHE of the Paris Bourse and on the NASDAQ
     Euroclear: 5433 - NASDAQ:  GENXY - Bloomberg: GNST FP - Reuters: GEN.F


                                      -end-


                                   SIGNATURES

     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.



                                         SERONO S.A.
                                         a Swiss corporation
                                         (Registrant)



October 31, 2002                         By:      /s/ Jacques Theurillat
                                         Name:    Jacques Theurillat
                                         Title:   Deputy Chief Executive Officer