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Form 6-K

SECURITIES AND EXCHANGE COMMISSION
Washington, D.C. 20549

Report of Foreign Private Issuer
Pursuant to Rules 13a-16 or 15d-16 of
the Securities Exchange Act of 1934

Dated: April 5, 2004

ALTANA Aktiengesellschaft
(Translation of registrant’s name into English)

Am Pilgerrain 15
D-61352 Bad Homburg v. d. Höhe
Federal Republic of Germany
(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 þ      Form 40-F o

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): o

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): o

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 o      No þ

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

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     This Report on Form 6-K is hereby incorporated by reference into the Registrant’s Registration Statements on Form S-8, dated September 13, 2002 (File No. 333-99485) and dated September 24, 2003 (File No. 333-109074)

     This Report on Form 6-K contains:

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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: April 5, 2004

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