No equitable defences in inter partes review

On September 23 2016 the Federal Circuit in Husky Injection Molding Systems Ltd v Athena Automation Ltd let stand a Patent Trial and Appeal Board (PTAB) ruling that the assignor estoppel barred the petitioner from filing an inter partes review petition. In its institution decision, the PTAB had reasoned that equitable doctrines, such as assignor estoppel, did not provide an exception to the broad statutory mandate that any person that is not an owner of a patent may file a petition to institute an inter partes review proceeding. The Federal Circuit let the PTAB decision stand, holding that it did not have jurisdiction over that aspect of the appeal.

Husky's patent was directed to a moulding machine with a clamp assembly. Husky's former owner and president, as a co-inventor of the patent, had assigned the patent to Husky. Shortly thereafter, he sold Husky and left to form Athena. Several years later, Athena filed the petition for inter partes review, challenging the patentability of all the claims. Husky filed a preliminary response, asserting only that assignor estoppel barred Athena from filing the petition. The PTAB rejected that argument and instituted review. 

In its final decision, the PTAB reached a mixed result, finding some of the claims valid and some invalid. Husky appealed the PTAB's decision with respect to the claims that had been found invalid, while Athena appealed with respect to the claims that had been found valid.

Husky's sole issue on appeal was whether assignor estoppel could bar a party from filing an inter partes review petition. Based on the Supreme Court's recent decision in In re Cuozzo Speed Technologies, the Federal Circuit held that it did not have jurisdiction to review the PTAB's institution decision under the statutory language precluding appeals. There are limited exceptions, such as permitting a challenge to the institution decision if related to the PTAB's ultimate authority to invalidate a particular patent, but the court held that this exception did not include the question of who was able to petition for review. 

To add salt to the wound, in the cross-appeal the Federal Circuit held that the PTAB had erred in its determination that certain claims were valid and not anticipated by the prior art. The court vacated and remanded to the PTAB for further evaluation.