Paul, Weiss
Firm overview:
Major US business law firm Paul, Weiss, Rifkind, Wharton & Garrison has a global footprint, with key offices in New York, Washington, DC, Los Angeles, San Francisco, Wilmington, London, Brussels, Tokyo, and Hong Kong. The firm focuses on high-stakes litigation, complex regulatory defence, and corporate advisory work. Paul Weiss’s use of technology in its legal practice includes the launch of generative artificial intelligence (genAI) tools in partnership with clients and tech-enabled work in e-discovery and transactional matters.
Paul Weiss’s patent litigation experience covers jury and bench trials, Section 337 disputes, appellate work, and Patent Trial and Appeal Board (PTAB) proceedings. The team has advised on patent matters relating to clients’ innovations in biologics, communications, consumer products, the life sciences, and industrial technologies.
Paul Weiss made headlines in 2025 when an executive order targeting the firm was rescinded following an agreement to provide $40 million of pro bono support to public causes. The White House also said the firm had agreed to audit its employment practices and disavow the use of diversity, equity and inclusion considerations.
Team overview:
Elizabeth Stotland Weiswasser is co-chair of Paul Weiss’s Litigation Department and one of the firm’s most prominent trial lawyers, with a practice that regularly involves disputes affecting life sciences, healthcare, and technology companies. She is widely known for leading complex, high-stakes patent and commercial litigation through trial and appeal, often where outcomes have downstream implications for patient access, product availability, or innovation incentives. Weiswasser joined Paul Weiss in 2024 from Weil, where she served as co-chair of litigation.
Anish Desai is a first-chair trial lawyer and leading PTAB practitioner at Paul Weiss, with extensive experience handling patent disputes across electronics, software, and medical-related technologies. He has served as lead counsel in more than 100 inter partes review proceedings and frequently coordinates parallel district court and appellate litigation. Desai joined the firm in 2024 from Weil and advises clients on patent validity and enforcement strategies.
Key matters:
- Altria Group v Juul Labs
Paul Weiss defended patents acquired by Altria that were challenged by Juul at the PTAB. Juul sought to invalidate patents important to Altria’s product portfolio. Paul Weiss convinced the board to issue two unanimous decisions upholding the validity of all challenged claims, rejecting Juul’s invalidity arguments and strengthening Altria’s patent position in ongoing competition.
- Regeneron v Mylan et al
Counsel from Paul Weiss were on the team representing Regeneron in its dispute with Mylan Pharmaceuticals, Amgen, and others over blockbuster eye treatment Eylea.
Clients:
Altria Group, Qualcomm, Regeneron
