Brian R. Matsui

Brian Matsui co-chairs Morrison Foerster’s Appellate and Supreme Court practice. Brian is a go-to appellate advocate for sophisticated clients in complex appeals. 

Brian has a nationwide appellate practice. He has argued many cases in federal and state appellate courts throughout the country, winning appeals involving federal preemption, securities litigation and enforcement, consumer class actions, and intellectual property. He has led appeals in the D.C., Second, Fourth, Fifth, Ninth, Eleventh, and Federal Circuits. His arguments include significant victories in class action appeals and in appeals for leading financial services companies, with multiple victories in the Ninth Circuit, where he clerked. Brian recently has gone five for six when representing appellants, including a precedential victory in the Ninth Circuit in a licensing dispute concerning alleged patent misuse. He also argued and won a D.C. Circuit appeal against the Securities and Exchange Commission (SEC) about the retroactivity of part of the Dodd-Frank Act. As a result of Brian’s win, the SEC had to change its enforcement practices against certain securities industry professionals.

Clients frequently turn to Brian for his substantial experience with appeals in the Federal Circuit, praising him as “an invaluable advocate in patent matters” (Chambers USA). Brian has won 13 of his last 15 appeals in that Court. His arguments before the Federal Circuit include winning appeals from district courts, the Patent Trial and Appeal Board, and the International Trade Commission. He has handled appeals in a myriad of industries, including mobile devices, pharmaceuticals, medical devices, semiconductors, and software.

Brian also plays a key role on trial teams, advising clients on both critical legal issues and appellate preservation. He recently argued and prevailed against a summary judgment invalidity motion in a case involving Chugai Pharmaceutical Co. Ltd.’s revolutionary antibody recycling technology, which ultimately led to a $775 million settlement on the eve of trial for Chugai.

A former law clerk for the United States Supreme Court, Brian has authored many briefs in that Court, including on important constitutional and statutory interpretation issues. He often represents clients’ interests in amicus briefs in significant Supreme Court cases affecting the business community.