An Alabama law firm has launched a class action on behalf of patent owners who’ve lost claims during America Invents Act proceedings.

Birmingham-based Heninger Garrison Davis argues in Christy v. United States. that the U.S. Patent and Trademark Office is taking property without just compensation every time it cancels claims in a post-grant proceeding. The U.S. Supreme Court seemed to sketch out such a theory in its Oil States Energy Services v. Greene’s Energy decision last month that turned away a broader constitutional challenge to inter partes review.