Peter A. Salz, a Genentech Inc. stockholder,...

Peter A. Salz, a Genentech Inc. stockholder, filed a class-action suit against the South San Francisco-based firm, alleging that officers of the pioneering biotechnology company were guilty of insider trading in connection with the sale of $20 million in stock. The suit was one of several filed in the past two weeks. Salz filed the lawsuit in U.S. District Court for Northern California and named Genentech and eight officers as defendants, as well as Lei Holdings and subsidiaries Lubrizol Corp. and Lubrizol Enterprises, Inc., all of whom allegedly owned large chunks of Genentech stock.