Brian M. Rosenthal

Brian M. Rosenthal is a highly experienced patent litigator and a partner in the New York office of Gibson, Dunn & Crutcher LLP, where he is a member of the Intellectual Property practice group. His practice focuses on complex patent litigation, spanning a wide range of technologies including computer software, electronics, and medical devices. He also has experience with computer networks, mobile telephone technology, e-commerce software, and call center technology. Rosenthal began his legal career at Howrey in 2000, later serving as a partner at Mayer Brown for nearly six years before joining Gibson Dunn in 2017.

With over 125 patent cases litigated, most as lead counsel, Rosenthal primarily represents operating companies as a defense litigator. His track record includes leading and winning multiple jury trials and arbitrations, as well as arguing and winning several patent cases before the Court of Appeals for the Federal Circuit. Notable victories include securing a complete defense verdict for Cisco in WSOU v. Cisco, which featured the first known jury verdict under 35 U.S.C. § 273 (prior commercial use defense), and a rare Rule 50(a) directed verdict for Cisco in Corrigent v. Cisco, ending a $376 million case. He also achieved a "clean-sweep trifecta jury win" for Duo Security in a $140 million multifactor authentication case. Further successes include winning inter partes reexaminations invalidating golf ball patents for Acushnet against a $246 million claim and invalidating an eCommerce patent under 35 U.S.C. § 101 for Google, affirmed by the Federal Circuit.

Rosenthal possesses substantial experience in Patent Office validity proceedings, including inter partes review (IPR) and post-grant review (PGR) petitions, often pursued concurrently with high-stakes litigation. He successfully argued and won inter partes reexaminations for Acushnet and filed and argued three Covered Business Method (CBM) petitions for Google, leading to the invalidation of all asserted claims.

He is admitted to the New York and District of Columbia Bars. Rosenthal earned his J.D. magna cum laude from Cornell University and holds a B.Sc. Honours in Computer Science, with a minor in Economics, from the University of Western Ontario.