In order to assist California defense attorneys in anticipating the claims against which they may have to defend, we provide weekly, unofficial summaries of the legal categories for new class actions filed in California state and federal courts in the Los Angeles, San Francisco, San Jose, Sacramento, San Diego, San Mateo, Oakland/Alameda and Orange County areas. We include only those categories that include 10% or more of the class action filings during the relevant timeframe. Typically, labor law class action cases lead the list of new filings by a wide margin, and this past week is no exception. This report covers the time period from March 9 – March 15, 2007. Approximately 45 class action lawsuits were filed in these California state and federal courts during that time period, 17 of which involve labor law claims (38%). Unfair competition law (UCL) claims, which include false advertising class action cases, came in second with 8 new filings (18%). The only other category of cases to break the 10% threshold involved antitrust class action lawsuits with 7 new filings (16%).