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 June, 2003

                                  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 if the registrant is submitting the Form 6-K in
paper as permitted by Regulation S-T Rule 101 (b)(1).)
                                                       ------

     (Indicate by check mark if the registrant is submitting the Form 6-K in
paper as permitted by Regulation S-T Rule 101 (b)(7).)
                                                       ------

     (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-      )
                                                 ------



                                                                          SERONO


Media Release


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


          SERONO COMPLETES ACQUISITION OF 100% OF GENSET SHARE CAPITAL

                        GENSET SHARES AND BONDS DELISTED


GENEVA,  SWITZERLAND  -  June 16, 2003 - Serono S.A. announced today that it had
completed  the  acquisition  of  all  the  previously  outstanding  shares  and
convertible  bonds  (known  as  OCEANEs)  of  Genset  S.A.

Upon the expiration on Friday, June 13, of the tender offers commenced by Serono
France  Holding on May 15, Serono France Holding accepted all shares and OCEANEs
tendered. 226,999 shares and 36 OCEANEs were tendered in the offer in France and
28,657 shares, including shares represented by 80,979 ADSs, were tendered in the
offer  in  the United States. Serono France Holding has made arrangements to pay
for  all  minority  interests  tendered.

As  previously  announced,  under applicable French law, the second-step squeeze
out  of  all  remaining  minority  interests  takes effect today.  All remaining
minority  interests  cease  to  have  an  equity interest in Genset.  Holders of
shares  and OCEANEs are now only entitled to receive consideration in the amount
of  EUR 8.19 per share and EUR 107.05 per OCEANE, respectively.  Holders of ADSs
are  now only entitled to receive consideration in the amount of the U.S. dollar
equivalent  of  EUR  2.73  per ADS, less any amount payable by the holder to the
depositary  of  the  ADR  program.  ADS holders will also be entitled to receive
from  the  depositary  their  pro rata portion of the net cash proceeds from the
sale of rights in connection with Genset's capital increase in March 2003.  As a
result,  Serono  France  Holding  now  owns  100%  of  the Genset share capital.

Genset shares and OCEANEs have been delisted from the Euronext market.


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  over  30  projects  in development.

Serono  was  awarded the International James D. Watson Helix 2003 Award from the
Biotechnology  Industry  Organization  (BIO)  in  recognition  of  the Company's
outstanding  leadership  and  highest  standards  of  scientific  and  product
achievement.


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In  2002,  Serono  achieved  worldwide  revenues  of US$1.546 billion, and a net
income  of  US$321  million,  making it the third largest biotech company in the
world.  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).


FOR MORE INFORMATION, PLEASE CONTACT:

SERONO IN GENEVA, SWITZERLAND:
MEDIA RELATIONS:                INVESTOR RELATIONS:
Tel:  +41-22-739 36 00          Tel:  +41-22-739 36 01
Fax:  +41-22-739 30 85          Fax:  +41-22-739 30 22
http://www.serono.com           Reuters: SEOZ.VX / SRA.N
---------------------           Bloomberg: SEO VX / SRA US

SERONO, INC., ROCKLAND, MA
MEDIA RELATIONS:                INVESTOR RELATIONS:
Tel.  +1 781 681 2340           Tel.  +1 781 681 2552
Fax:  +1 781 681 2935           Fax:  +1 781 681 2912
http://www.seronousa.com
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                                   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)



June 16, 2003                      By:   /s/ Allan Shaw
                                         -----------------
                                         Name:  Allan Shaw
                                         Title: Chief Financial Officer