Federal Circuit Summary

Before Prost, Schall, and Chen. Appeal from the Patent Trial and Appeal Board.

Summary: The plain language of 35 U.S.C. § 311(a) unambiguously leaves no room for assignor estoppel to apply in the IPR context.

Dr. David Cheriton is the named inventor of U.S. Patent No. 7,340,597 (“the ’597 patent”), which is owned by Cisco Systems, Inc. At the time of invention, Dr. Cheriton was employed by Cisco and assigned the invention claimed in the ’597 patent to Cisco. Dr. Cheriton later left Cisco and founded Arista Networks, Inc.

Arista petitioned for IPR of certain claims of the ’597 patent. After instituting the IPR, the PTAB upheld some of the challenged claims as patentable but invalidated others. On appeal, Arista argued that the Board erred in construing the term “broadcast” and that this error caused the Board to improperly reject Arista’s obviousness challenge to certain claims of the ’597 patent. Cisco cross-appealed, arguing that the Board erred in refusing to apply the doctrine of assignor estoppel.

The Federal Circuit reversed and remanded with respect to Arista’s appeal and affirmed with respect to Cisco’s cross-appeal. The Federal Circuit noted that the Board’s construction of “broadcast” could not stand because it ignored the patentee’s use of the term and excluded the only explicitly disclosed embodiment of broadcasting found in the ’597 patent. Instead, the Federal Circuit construed the term consistent with its use in the specification and remanded the case for the Board to reconsider the claims at issue in view of the new claim construction.

With respect to Cisco’s cross-appeal, the Federal Circuit first considered whether the issue of assignor estoppel was reviewable on appeal. Applying the Supreme Court’s decision in Cuozzo Speed Techs., LLC v. Lee, 136 S. Ct. 2131 (2016) and the Federal Circuit’s decision in Wi-Fi One, LLC v. Broadcom Corp., 878 F3d 1364 (Fed. Cir. 2018) (en banc), the Federal Circuit concluded that the application of assignor estoppel in the IPR context is reviewable because it is unrelated to the preliminary patentability assessment or the exercise of discretion not to institute. The Court next considered whether assignor estoppel applied in the IPR context. In view of 35 U.S.C. § 311(a), which allows “a person who is not the owner of a patent” to file an IPR, the Federal Circuit concluded that Congress unambiguously left no room for assignor estoppel to apply in the IPR context.

This case is: ARISTA NETWORKS, INC. v. CISCO SYSTEMS, INC.

Editor: Paul Stewart

Written by: Benjamin Ho & Andrea Cheek