Mark A. Klapow

Mark A. Klapow is a Chambers-ranked trial lawyer specializing in high-stakes intellectual property and technology disputes, with over 25 years of experience. He is a partner in Crowell & Moring's Washington, D.C. office, where he focuses on "bet the company" litigation for startups and Fortune 500 companies. Klapow is particularly recognized for his work in technology and trade secret litigation, handling cases involving artificial intelligence, enterprise software, financial services, and other emerging technologies. His practice also extends to antitrust and complex commercial disputes.

Klapow primarily represents defendants, as indicated by his tracked case appearances. He has defended major corporations such as Alcoa, AT&T, Caterpillar, Dow Chemical, Ericsson, ExxonMobil, Intel, Lenovo, Molson Coors, StoneX, and Western Union. Prior to joining Crowell & Moring in March 2011, Klapow was a partner at Howrey LLP.

A prominent recent success for Klapow includes leading a team that secured a unanimous eight-figure jury verdict in May 2026 for client C3.ai in an AI trade secret misappropriation case against Cummins Engine Co. in Delaware state court. He also achieved a favorable resolution for Lenovo in trade secret litigation against a former vendor in California federal court in 2021. While the provided case list indicates an appearance as Lead Counsel for the defendant in Champion Power Equipment Inc. v. Harbor Freight Tools USA Inc., associated with Gibson, Dunn & Crutcher, web searches for this case (filed October 2024) and Mr. Klapow's firm history place him at Crowell & Moring since 2011. Court dockets for Champion Power Equipment Inc. v. Harbor Freight Tools USA Inc. (2:24-cv-01302 E.D. Wis.) do not list Mark A. Klapow as counsel for Harbor Freight. The Wisconsin district court case was dismissed based on a first-to-file rule, with the substantive patent dispute proceeding in the Central District of California. Crowell & Moring's patent litigation practice has experience with Post-Grant Proceedings and U.S. International Trade Commission (ITC) Section 337 cases, as well as Hatch-Waxman matters.

Klapow earned his B.A. from Washington University in St. Louis in 1996 and his J.D., cum laude, from Syracuse University College of Law in 1999. He is admitted to practice in the District of Columbia and New York, and before the U.S. Court of Appeals for the Federal Circuit and the U.S. Court of Appeals for the First Circuit.