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

Shareholders Sue Columbia S&L; Directors: A shareholder, Walter Untermeyer Jr., filed suit in Los Angeles Superior Court Monday against former and current officers and directors of Columbia Savings & Loan, claiming that their investment in “high-risk speculative junk bonds” on behalf of the thrift amounted to reckless disregard of their duty. Columbia held $3.7 billion in junk bonds, or 40% of its total assets. (Filed March 5; Case No. C754084)