Jim Pistorino has updated his annual BNA report on patent lawsuit case filings. His biggest finding is that the new joinder provisions of the America Invents Act (AIA) appear to have had a major impact on the distribution of new lawsuit filings.

The new joinder rules became effective for all patent lawsuits filed on or after September 16, 2012 and limit the ability of a plaintiff to join multiple unrelated defendants in a single action. In addition to potential cost savings of a single-suit, the joining of geographically diverse defendants in a single suit is thought to make it more difficult for one of the defendants to force a transfer of venue. Thus, the idea behind limiting the joinder of unrelated defendants is that it may allow courts to more easily transfer venue and thus shift filing focus away from the Eastern District of Texas.

The punch line here from the preliminary data through December 2011 is that (1) post-AIA filings have dropped in the Eastern District of Texas and risen in other districts, namely Delaware; (2) more cases are now being filed in Delaware than any other district; (3) more defendants are being sued in Delaware than any other district. Prior to AIA, E.D. Texas was the clear leader in these categories; and (4) overall the number of defendants being sued has decreased.

Read the article: 2011 Trends in Patent Case Filings by James C. Pistorino and Susan Crane.