Federal Circuit: Assignor Estoppel Not Available In Inter Partes Review

Mealey's (November 13, 2018, 1:06 PM EST) -- WASHINGTON, D.C. — A panel of the Federal Circuit U.S. Court of Appeals on Nov. 9 upheld findings by the Patent Trial and Appeal Board that Arista Networks Inc. is not barred by the doctrine of assignor estoppel from challenging the validity of a Cisco Systems Inc. patent because assignor estoppel is unavailable for assertion in an inter partes review (IPR) proceeding (Arista Networks Inc. v. Cisco Systems Inc., Nos. 17-1525, -1577, Fed. Cir., 2018 U.S. App. LEXIS 31808)....