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FORM 6-K
SECURITIES AND EXCHANGE COMMISSION
Washington, D.C. 20549

Report of Foreign Issuer

     Pursuant to Rule 13a-16 or 15d-16
of the Securities Exchange Act of 1934

For the month of May 2006

Commission File Number: 001-15152

SYNGENTA AG
(Translation of registrant’s name into English)

Schwarzwaldallee 215
4058 Basel
Switzerland
(Address of principal executive offices)

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 by furnishing the information contained in this Form, the Registrant is also thereby furnishing the information to the Commission pursuant to Rule 12g3-2(b) under the Securities Exchange Act of 1934:

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

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Re:	SYNGENTA AG
	Disclosure of share ownership

Filed herewith is a notification of share ownership related to Syngenta AG. The full text of the notification follows:

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Disclosure of share ownership

The shareholding in Syngenta AG of Janus Capital Management LLC exceeds the threshold value of 5%

Based on Article 20 of the Swiss Stock Exchange Act, Syngenta AG has received the following notification from Janus Capital Management LLC:

Janus Capital Management LLC, 151 Detroit Street, Denver, Colorado, USA reported an exceeding of the reporting threshold value of 5% and is holding a total of 5.07% of the share capital of Syngenta AG.

In compliance with Article 19 of the Swiss Stock Exchange Ordinance-FBC this information will be published in the Swiss Official Gazette of Commerce.

Syngenta AG
Basel, Switzerland, May 17, 2006

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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.

		SYNGENTA AG
Date:	May 17, 2006	By:	/s/ Christoph Mäder
			Name:	Christoph Mäder
			Title:	Head Global Legal and Taxes
		By:	/s/ Damian Heller
			Name:	Damian Heller
			Title:	Company Secretary