The concentration of patent filings in these two districts has increased this year, and through 10 September, Delaware was the top spot for new patent cases in 2013, with 1,015 new cases, just ahead of the 920 cases filed in the Eastern District of Texas, according to an analysis conducted by Perkins Coie partner James Pistorino.

The analysis looked at district court filings only, not including the International Trade Commission. It showed a continuation of the steady increase since 2008 with acceleration since the implementation of the America Invents Act earlier this year. Delaware in particular is surging, the findings show, with a projected 50 percent increase this year over 2012.

It is difficult to point to a particular reason for Delaware’s increase, Pistorino told Intellectual Property Watch by email. ”First, there has not been any fall off in how popular the Eastern District of Texas has been.,” he said. ”Instead, it is just that Delaware has become more popular than it was and about 6% more of the nationwide total of cases filed in districts other than the Eastern District of Texas are being filed in Delaware. The Delaware courts continue to be reluctant to transfer cases. Thus, plaintiffs may assess that the risk of transfer out of Delaware is lower than was thought in 2011 and the early part of 2012 thus making Delaware more attractive.”

Overall cases are on track to rise by 10 percent this year, the analysis said, though the number of defendants named in those cases appears likely to remain the same.