Patent assertion entities seem so 2012. Businesses that acquire patents and then enforce them—sometimes criticized as “patent trolls”—have largely dropped out of the headlines since the America Invents Act (AIA) and the Supreme Court’s Alice decision simplified the process of challenging patent validity in many cases.

But PAEs, as they’re also known, haven’t disappeared from the litigation radar altogether. Some have been attracting big new investment while others have reorganized and started reviving litigation campaigns. This comes as the Patent Trial and Appeal Board has become slightly less willing, statistically, to cancel patents in AIA proceedings, and the U.S. Court of Appeals for the Federal Circuit has added more gloss to the Alice v. CLS Bank International decision.