Tuesday, Apr 6, 2004

Genentech Win in Chiron Patent Litigation Unanimously Affirmed by U.S. Court of Appeals

South San Francisco, Calif. -- April 6, 2004 --

Genentech, Inc. (NYSE: DNA) today announced that a three-judge panel of the U.S. Court of Appeals for the Federal Circuit unanimously affirmed the 2002 judgment of a U.S. District Court that found in favor of Genentech that all claims of Chiron Corporation's U.S. Patent No. 6,054,561 asserted against Genentech are invalid. Chiron sued Genentech for alleged infringement of its patent by Genentech's metastatic breast cancer drug, Herceptin® (Trastuzumab).

"We are encouraged that the court recognized the strength of our position on this appeal," said Stephen G. Juelsgaard, D.V.M., J.D., executive vice president, general counsel and secretary at Genentech. "Genentech is committed to vigorously defending its products and its intellectual property positions."

Genentech is a leading biotechnology company that discovers, develops, manufactures and commercializes biotherapeutics for significant unmet medical needs. Eighteen of the currently approved biotechnology products originated from or are based on Genentech science. Genentech manufactures and commercializes 13 biotechnology products in the United States. The company has headquarters in South San Francisco, California and is traded on the New York Stock Exchange under the symbol DNA. For additional information about the company, please visit http://www.gene.com.