Douglas Ethan Lumish

Douglas Ethan Lumish is Co-Head of Weil, Gotshal & Manges' nationwide IP, Technology & Science Litigation practice, focusing on high-stakes intellectual property, technology, and life sciences-related disputes. His practice encompasses patent, trade secret, contract, licensing, and fraud cases across diverse technology areas, including high-tech, biotechnology, and AI. Notable representations involve cross-device user identification and ad-effectiveness measurement technology, such as in Intent IQ, LLC v. MNTN, Inc.. He regularly acts as lead strategic and trial counsel for sophisticated technology and life sciences companies.

Lumish frequently defends operating companies, with his tracked appearances exclusively on the defendant side (1 defendant, 0 plaintiff appearances). His experience includes securing favorable outcomes for clients, often involving defeating substantial claims. For example, he was lead trial counsel for Amazon in a summary judgment win against Telebuyer and for Google and YouTube in a case that resulted in a jury verdict of patent invalidity against the University of California and Eolas, defeating claims for hundreds of millions of dollars related to interactive web pages. He also achieved a reversal of a $600 million patent verdict against Gen Digital at the Federal Circuit. Further significant defense work includes summary judgment victories for Meta against MasterObjects and for WhatsApp against TriPlay, as well as trial wins in the ITC for Arista Networks against Cisco. His practice also extends to trade secret misappropriation claims, such as representing AbbVie Inc. against Alvotech hf and defending Rivian Automotive Inc. against Tesla Inc.'s claims.

Lumish began his legal career at Weil, Gotshal & Manges, spending 15 years there before taking on leadership roles at other major global law firms, including 12 years at Latham & Watkins and a period at Kasowitz Benson Torres & Friedman. He returned to Weil, Gotshal & Manges as Co-Head of their IP, Technology & Science Litigation practice. While not explicitly stated that he regularly appears in IPR/PGR proceedings, his firm, Weil, Gotshal & Manges, is noted for its strong track record in PTAB procedures, including IPRs. He also provides insight into the impact of the IPR process on patent litigation.

He was admitted to the State Bar of California in December 1996, having earned his J.D. from Santa Clara University School of Law in 1996.