Form 6-K SECURITIES AND EXCHANGE COMMISSION Washington, D.C. 20549 Report of Foreign Private Issuer Pursuant to Rule 13a-16 or 15d-16 of the Securities Exchange Act of 1934 For the month of January, 2006 CONVERIUM HOLDING AG ----------------------------------------------- (Translation of registrant's name into English) Baarerstrasse 8 CH-6300 Zug Switzerland ---------------------------------------- (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 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 the file number assigned to the registrant in connection with Rule 12g3-2(b): 82- Not Applicable Odey Asset Management LLP adjusts its holding in Converium registered shares from 11.2% to 5.3% Disclosure of shareholdings pursuant to Art. 20 SESTA Converium Holding Ltd, Zug, has been notified that Odey Asset Management LLP, 12 Upper Grosvenor Street, London W1K 2ND, United Kingdom, has decreased its holding of registered shares with voting rights to 7,776,446. This corresponds to 5.3% of Converium's registered share capital. These shares are held and managed in various funds. None of these funds is holding shares in an amount, which exceeds 5% of Converium's registered share capital. Odey Asset Management LLP is a British Financial Services Authority registered fund management house, and acts as the investment manager for several funds. Zug, January 17, 2006 Contacts: Zuzana Drozd Head of Investor Relations zuzana.drozd@converium.com -------------------------- Phone +41 (0) 44 639 91 20 Fax +41 (0) 44 639 71 20 Esther Gerster Head of Public Relations esther.gerster@converium.com ---------------------------- Phone +41 (0) 44 639 90 22 Fax +41 (0) 44 639 70 22 www.converium.com ----------------- 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. CONVERIUM HOLDING AG By: /s/ Terry Clarke ---------------- Name: Terry Clarke Title: CEO By: /s/ Christian Felderer ---------------------- Name: Christian Felderer Title: General Legal Counsel Date: January 17, 2006