In my last post, I discussed estoppel in the context in inter partes review, in which defendant filed for IPR after losing in the courts. The Board found the claims-in-suit to be obvious. The Federal Circuit affirmed that the courts and the PTAB could reach different conclusions about patentability.

In Fairchild (Appeal no. 17-1002 (Fed. Cir., April 21, 2017)), the Federal Circuit found the asserted claims to be valid. Power Integrations had earlier filed for inter partes reexamination, using the same references it used in the District Court suit. The Federal Circuit ordered the PTAB to vacate and dismiss the reexamination of the claims found to be valid. Note that this decision rests on the provisions of 35 USC s. 317, which prevents a defendant that lost on invalidity in the courts from bringing the same challenge via inter partes reexamination. Section 317 (pre-AIA) is worded differently than Section 315(e)(2), relating to inter partes review estoppel. Post-AIA, defendant can lose at the district court but faces broad estoppel if it pursues IPR –although, (as in Novartis v. Noven) it can still prevail even if the records are identical (!) My head hurts!