UNITED STATES
                       SECURITIES AND EXCHANGE COMMISSION
                             WASHINGTON, D.C. 20549
                               ------------------
                                    FORM 6-K

                        REPORT OF FOREIGN PRIVATE ISSUER
                        PURSUANT TO RULE 13a-16 OR 15d-16
                    UNDER THE SECURITIES EXCHANGE ACT OF 1934
                               ------------------
                          For the month of August 2004

                        Commission File Number: 001-31368

                                 SANOFI-AVENTIS
                 (Translation of registrant's name into English)

                   174, avenue de France, 75013 Paris, FRANCE
                    (Address of principal executive offices)

         Indicate by check mark whether the registrant files or will file annual
reports under cover 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" marked, indicate below the file number assigned to the
registrant in connection with Rule 12g3-2(b): 82-________






SANOFI-AVENTIS



PARIS, AUGUST 23, 2004



MANDATORY  PUBLICATION  PURSUANT  TO  SECTIONS  35  SUB-SEC.  1, 10  SUB-SEC.  3
SECURITIES ACQUISITION AND TAKEOVER ACT (WPUG) - MANDATORY OFFER



Offeror:

Sanofi-Aventis
174 avenue de France
75013 Paris
France

ISIN FR 0000120578 (WKN 920 657)



Target:

Hoechst Aktiengesellschaft
Industriepark Hoechst, Gebaude K 701
BruningstraBe 50
65926 Frankfurt am Main
Germany

ISIN DE 0005758007 (WKN 575 800)



Other Companies directly affected by the Mandatory Offer:

Aventis
Cedex 9
67917 Strasbourg
France

ISIN FR 0000130460 (WKN 925 700)



Sanofi-Aventis,  a French stock corporation (SOCIETE ANONYME),  hereby announces
pursuant to Sections 35 sub-sec.  1, 10 sub-sec.  3 Securities  Acquisition  and
Take-over  Act ("WpUG")  that by  acquisition  of the majority of the shares and
voting rights of Aventis, a French stock corporation  (SOCIETE  ANONYME),  on 20
August 2004, it gained indirect control in the meaning of Section 29 sub-sec.  2
WpUG over Aventis'  subsidiary Hoechst  Aktiengesellschaft  (ISIN DE 0005758007,
WKN 575 800).


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Aventis  holds a total of  548,451,852  of the  559,153,690  shares  of  Hoechst
Aktiengesellschaft.  This represents  98.09% of the registered share capital and
the voting rights in Hoechst Aktiengesellschaft.

Following the acquisition of the majority  participation in Aventis these voting
rights  in  Hoechst  Aktiengesellschaft  are now  attributed  to  Sanofi-Aventis
pursuant to Section 30 sub-sec. 1 sentence 1 no. 1 WpUG.

Through  the   acquisition   of  the  majority   participation   in  Aventis  by
Sanofi-Aventis  on 20 August 2004,  Total, a French stock  corporation  (SOCIETE
ANONYME), 2 place de la Coupole, 92078 Paris La Defense Cedex, France,  L'Oreal,
a French  stock  corporation  (SOCIETE  ANONYME),  14 rue Royale,  75008  Paris,
France,  Tethys SAS, a French partnership limited by shares (SOCIETE PAR ACTIONS
SIMPLIFIEE),  14 rue Royale,  75008 Paris,  France, Ms Liliane  Bettencourt,  Mr
Andre Bettencourt,  Ms Francoise Bettencourt Meyers, Mr Jean-Pierre Meyers (each
of these  individual  shareholders  with address at 14 rue Royale,  75008 Paris,
France),  and Nestle S.A., a Swiss stock corporation  (SOCIETE ANONYME),  avenue
Nestle 55  CH-1800  Vevey,  Switzerland,  also  gained  indirect  control in the
meaning of Section  29  sub-sec.  2 WpUG over  Hoechst  Aktiengesellschaft.  The
548,451,852 shares or 98.09% of the voting rights in Hoechst  Aktiengesellschaft
held by Aventis are also  attributed to each of Total,  L'Oreal,  Tethys SAS, Ms
Liliane Bettencourt,  Mr Andre Bettencourt,  Ms Francoise Bettencourt Meyers, Mr
Jean-Pierre  Meyers and Nestle S.A. pursuant to Section 30 sub-sec. 1 sentence 1
no. 1 WpUG.

Satisfying its obligations and the obligations of Total, L'Oreal, Tethys SAS, Ms
Liliane Bettencourt,  Mr Andre Bettencourt,  Ms Francoise Bettencourt Meyers, Mr
Jean-Pierre   Meyers  and  Nestle   S.A.   resulting   from   Section  35  WpUG,
Sanofi-Aventis  will  make a  mandatory  offer to the  outside  shareholders  of
Hoechst Aktiengesellschaft.

Subsequent to the approval by the German Federal Financial Supervisory Authority
(BUNDESANSTALT  FUR  FINANZDIENSTLEISTUNGSAUFSICHT)  the offer  document for the
mandatory  offer will be  published  pursuant  to  Sections  35  sub-sec.  2, 14
sub-sec. 3 sentence 1 no. 1 WpUG on the Internet at

                          http://www.sanofi-aventis.com

and by public announcement of its free of charge availability.

Sanofi-Aventis    reserves   the   right   to   purchase   shares   in   Hoechst
Aktiengesellschaft  outside the mandatory  offer as permitted  under German law,
provided such purchases shall not violate any applicable  securities laws of any
other jurisdiction.  The offer document and announcements posted on the internet
at http://www.sanofi-aventis.com will contain further information about any such
purchases outside the mandatory offer.

This announcement is neither an offer to purchase nor a solicitation of an offer
to sell securities of Hoechst Aktiengesellschaft. The offer will be contained in
the offer document which will contain additional important information.

This announcement contains forward looking statements,  which may be identified,
inter  alia,  by words  such as  "intends",  "anticipates",  "will"  or words of
similar  meaning.  These  statements  are based on the current  expectations  of
Sanofi-Aventis  and are  inherently  subject  to  uncertainties  and  changes in
circumstances,  many of which are outside Sanofi-Aventis' control. Actual events
could differ materially from those described in the forward looking  statements.
Except as required by  applicable  law,  Sanofi-Aventis  does not  undertake any
obligation to update the  forward-looking  statements to reflect actual results,
or any change in events, assumptions or other factors.


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This  announcement  was submitted to the German  Federal  Financial  Supervisory
Authority  (BUNDESANSTALT FUR  FINANZDIENSTLEISTUNGSAUFSICHT;  BAFIN) and to the
French Authority for Financial  Markets (AUTORITE DES MARCHES  FINANCIERS;  AMF)
prior to the publication of this  announcement  pursuant to Sections 35 sub-sec.
1, 10 sub-sec.  4 WpUG and  article 7 of the  provision  no.  2002-04 of the COB
(Commission des operations de bourse), respectively.



23 August 2004



Sanofi-Aventis (for itself and for Total, L'Oreal, Tethys SAS, Ms Liliane
Bettencourt, Mr Andre Bettencourt, Ms Francoise Bettencourt Meyers, Mr
Jean-Pierre Meyers and Nestle S.A.)







Listings  of  Hoechst  Aktiengesellschaft,  Sanofi-Aventis  and  Aventis  in the
Federal Republic of Germany:

Hoechst   Aktiengesellschaft:    Official   Market   in   Frankfurt   am   Main,
Over-The-Counter  in Berlin-Bremen,  Dusseldorf,  Hamburg,  Hanover,  Munich and
Stuttgart.

Sanofi-Aventis:  Over-The-Counter  in  Berlin-Bremen,  Dusseldorf,  Frankfurt am
Main, Hamburg, Hanover, Munich and Stuttgart.

Aventis:   Official   Market  in   Frankfurt   am  Main,   Over-The-Counter   in
Berlin-Bremen, Dusseldorf, Hamburg, Hanover, Munich and Stuttgart.





INVESTOR RELATIONS DEPARTMENT
PHILIPPE GOUPIT         DIRECTOR OF INVESTOR RELATIONS
ARNAUD DELEPINE         INVESTOR RELATIONS EUROPE
SANJAY GUPTA            INVESTOR RELATIONS US
ANNE D'HALLUIN-SULZER   INVESTOR RELATIONS
LOIC GONNET             INVESTOR RELATIONS


CONTACTS:
EMAIL: investor-relations@sanofi-synthelabo.com
EUROPE                                  US
TEL : + 33 1 53 77 45 45                TEL.:   +1 212 551 40 18
FAX : + 33 1 53 77 42 96                FAX :   +1 646 487 40 18








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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.


Dated: August 24, 2004                    SANOFI-AVENTIS


                                          By:    /s/ Marie-Helene Laimay
                                             -----------------------------------
                                             Name:    Marie-Helene Laimay
                                             Title:   Senior Vice President and
                                                      Chief Financial Officer