The chart above comes from LexMachina [Link] and shows the number of lawsuits filed each month for the past several years. You’ll note that the number of case filings in January 2014 is the lowest since October 2011. The rise in filings since 2011 is largely (if not completely) explained by the joinder provisions of the AIA that block a patentee from filing suit against multiple unrelated parties in a single lawsuit.
This week Steve Morsa sued Facebook on his match-engine-marketing patents. See U.S. Patent Nos. 7,904,337 and 8,341,020; Adidas sued UnderArmor for infringing twelve of its patents covering location-aware fitness devices. See U.S. Patent Nos. 7,292,867 and 7,805,149; and Dyson sued Euro-Pro for infringing its U.S. Design Patent No. D668,010 that appears to cover the Dyson Digital cordless vacuum.