The United States Patent and Trademark Office in Washington, DC has issued US Patent No. 6,720,488. This patent is the fifth in a series of transgenic patents issued to Syngenta (NYSE: SYT) in the field of insect resistant corn. All five patents cover synthetic Bt genes that provide useful products to corn growers by conferring resistance to two economically important insect pests: the European corn borer (ECB) and the corn rootworm (CRW).

Three of the previously issued patents* are the subject of a lawsuit Syngenta filed on July 25, 2002 in Federal District Court in Wilmington, DE.

The lawsuit charges that Monsanto, DeKalb Genetics, Pioneer Hi-Bred, Dow AgroSciences and Mycogen Seeds are infringing one or more of these patents with their YieldGard(R) and Herculex(TM) product lines. The lawsuit is expected to go to trial in November 2004.

Syngenta has filed a new lawsuit in Federal District Court in Wilmington, DE seeking damages and injunctive relief against the same defendants for the infringement of the latest patent.

Syngenta is a world-leading agribusiness committed to sustainable agriculture through innovative research and technology. The company is a leader in crop protection, and ranks third in the high-value commercial seeds market. Sales in 2003 were approximately $6.6 billion. Syngenta employs more than 19,000 people in over 90 countries. Syngenta is listed on the Swiss stock exchange (SYNN) and in New York (SYT).

*US Patent No. 6,075,185, US Patent No. 6,320,100, and US Patent No. 6,403,865