US patent law gives defendants a variety of options for challenging patent validity within and outside district court, including through administrative proceedings brought before the USPTO. Yet when a party’s validity challenge reaches a final decision, that party is then limited in its ability to subsequently take certain related actions, including relitigating certain validity arguments in another proceeding—a principle known as estoppel that is reflected in the America Invents Act (AIA) and various regulations issued by the USPTO under that law. The Federal Circuit has now issued a new precedential decision, in SoftView v. Apple, that upheld one such regulation, one that prevents patent owners from “obtaining” claims that are “not patentably distinct” from claims invalidated by the Patent Trial and Appeal Board (PTAB)—a broader estoppel standard than the one that applies in district court. While the appellate court also found that the USPTO was within its authority to issue that regulation in the first place, it additionally determined that the PTAB had been wrong to find that the provision also bars “maintaining” existing claims that meet this same criterion.