Kramer Levin Naftalis & Frankel

Herbert Smith Freehills Kramer (HSF Kramer), formerly Kramer Levin Naftalis & Frankel LLP, is a transatlantic and transpacific law firm formed by a merger in June 2025. Headquartered in New York City, HSF Kramer maintains additional U.S. offices in Silicon Valley (Menlo Park, CA) and Washington, D.C., along with an international presence in Paris, France. Prior to the merger, Kramer Levin was recognized as an Am Law 200 firm, ranking #102 in 2022. Chambers USA consistently recognizes the firm for its Intellectual Property: Patent practice.

HSF Kramer's Intellectual Property practice is particularly active in patent litigation across diverse technology sectors. The firm demonstrates significant experience in electrical and computer technologies, telecommunications, network security, and software, as evidenced by its work in cases involving network threat detection and mobile device technologies. The practice also has noted strength in life sciences, including pharmaceuticals, molecular diagnostics, vaccines, and medical devices. While the firm represents both patent owners and defendants, its case portfolio indicates a primary focus on asserting patent rights, with 14 tracked plaintiff-side appearances compared to 5 defendant-side appearances.

The firm has achieved notable results in high-stakes patent disputes. Most prominently, HSF Kramer secured a $1.9 billion judgment for Centripetal Networks Inc. against Cisco Systems, Inc. in a cybersecurity patent case following a bench trial in October 2020. More recently, in January 2024, the firm obtained a $151.5 million jury award for Centripetal Networks against Palo Alto Networks, Inc. for infringement of network security patents. In other significant matters, the firm has represented WinView IP Holdings, LLC in patent infringement lawsuits against DraftKings and FanDuel concerning live-TV skill gaming technology. The firm also has experience defending against challenges, as seen in the Centripetal Networks v. Keysight Technologies, Inc. litigation, which involved multiple appeals to the Federal Circuit concerning PTAB decisions. Conversely, the firm was involved in appeals where Express Mobile, Inc.'s patents related to mobile web presentation and programming were affirmed as unpatentable by the Federal Circuit, concluding enforcement efforts against major tech companies.

HSF Kramer maintains an active practice before the Patent Trial and Appeal Board (PTAB), regularly engaging in both the assertion and defense of IP-related claims at the USPTO. This includes defending Centripetal Networks, LLC in IPR proceedings initiated by Unified Patents, LLC and appealing PTAB decisions to the Federal Circuit. Key partners leading the firm's intellectual property litigation efforts include Paul J. Andre, who serves as Managing Partner of the Silicon Valley Office and Head of Intellectual Property, U.S., and Jonathan S. Caplan, a co-chair of the IP practice. Lisa Kobialka and Aaron M. Frankel are also recognized as prominent patent litigation partners within the firm.