A summary of Southern California-related business litigation developments during the past week.

First Interstate Bank Sued: A shareholder suit charging that First Interstate Bancorp lied to its shareholders about the bank’s health and that it artificially maintained a high stock price was filed Tuesday in U.S. District Court in Los Angeles. The suit charges that the company’s restructuring plan begun in 1987 and that its merger with Allied Bancshares Inc. “resulted in a diminution of the overall quality of its loan portfolio,” which was hidden from shareholders. First Interstate had no comment on the suit. (Filed Jan. 2, 1990 Case No. CV90-0007 RMT)