Friday, Oct 22, 1999

Genentech 2-For-1 Stock Split Effective on October 29

South San Francisco, Calif. -- October 22, 1999 --

Genentech, Inc. (NYSE: DNA) today announced that the record date of its previously announced 2-for-1 stock split is October 29, 1999. All shareholders of record of Genentech stock at the close of business on that date will receive one additional share for each share held. The additional shares will be distributed beginning November 2, 1999. Genentech stock will trade on a split-adjusted basis on November 3, 1999.

Genentech previously announced that its board of directors approved a 2-for-1 split of its common stock to be effected in the form of a stock dividend. This stock split in addition to the secondary offering of 20 million shares by Roche on October 21, 1999 will nearly quadruple the number of publicly traded Genentech shares.

This announcement does not constitute an offer to sell or the solicitation of an offer to buy. There shall not be any sale of these securities in any state in which such offer, solicitation or sale would be unlawful prior to registration or qualification under the securities laws of any such state. Copies of the prospectus relating to the offering may be obtained from J.P. Morgan & Co., 60 Wall Street, New York, New York 10260, Attention: Prospectus Department.

Genentech, Inc. is a leading biotechnology company that discovers, develops, manufactures and markets human pharmaceuticals for significant unmet medical needs. Twelve of the approved products of biotechnology stem from Genentech science. Genentech markets seven products directly 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.

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