Winston & Strawn

Firm overview:

On January 30, 2026, Winston & Strawn sealed its merger with the UK-led business of Taylor Wessing, with partnership votes from both firms clearing the way for the launch of Winston Taylor in May 2026. For IP-intensive businesses, the deal signals the emergence of a firm positioned to advise across jurisdictions.

Winston & Strawn brings to the table a leading US patent litigation practice, which takes on high-stakes and technically complex disputes across multiple forums. The team is highly active in patent disputes, and defended clients in more patent trials than any other US law firm from 2020 to 2024; it has also handled more than 400 Patent Trial and Appeal Board (PTAB) proceedings. Recent wins before the International Trade Commission (ITC) include a complete defence victory on behalf of leading semiconductor company AMD.

Team overview:

Winston has over 90 attorneys focused on patent litigation. The team includes former district court and Federal Circuit clerks, assistant US attorneys, patent examiners, and IP attorneys with technical or scientific degrees.

A hallmark of the practice is Kathi Vidal, the former director of the US Patent and Trademark Office, who rejoined Winston & Strawn as a patent litigator and executive committee member at the end of 2024. Her work this year has spanned leading efforts in emerging artificial intelligence (AI)-related litigation and policy matters and shaping strategic counsel for clients navigating uncertain technology-driven landscapes.

Brett Johnson heads the Litigation Practice for the Dallas office and handles all aspects of complex commercial and IP litigation. Johnson’s experience spans industries including high-tech, banking, and pharmaceutical, and he has obtained favourable litigation/arbitration results for clients including xAI, Toyota, Ericsson and First United Bank.

In Chicago, George Lombardi, Fellow of the American College of Trial Lawyers, is recognised for his litigation skills, which have enabled him to secure trial wins in matters involving top-selling drugs such as Prozac, Yasmin, Baraclude and Temodar. Lombardi has worked on key firm successes with Ivan Poullaos. Poullaos holds a degree in chemistry and represents pharmaceutical companies in biologics and small molecule infringement cases.

Chuck Klein, the litigation office head in Washington, DC, focuses on high-stakes proceedings related to mRNA technology, the BPCIA, and the Hatch-Waxman Act. Klein has worked alongside Claire Fundakowski, a pharmacist and former Federal Circuit clerk who represents clients in matters involving injectable, oral, and topical pharmaceutical compositions.

Key matters:

• Amarin Pharma et al v Hikma Pharmaceuticals USA et al

In 2022, Winston secured a victory for Hikma when the district court granted its motion to dismiss Amarin’s infringement claims for failure to state a claim. Winston successfully argued that Hikma’s generic product “carved out” the cardiovascular indication and that Hikma’s marketing and public statements had not induced infringement of Amarin’s patents.

Winston represented Hikma in Amarin’s appeal. On June 25, 2024, the Federal Circuit reversed the lower court’s decision, sending the case back to the District of Delaware.

Hikma petitioned the Supreme Court for review in February 2025.

The issue has attracted significant attention, and the Association for Accessible Medicines (AAM) and 30 scholars of law, economics, and medicine have filed briefs as amici curiae to support the petition. On June 23, 2025, the Supreme Court asked the solicitor general to weigh in.

The team is Chuck Klein, Claire Fundakowski, and Eimeric Reig-Plessis.

• Corning v John Wilson and Wilson Wolf Manufacturing

In September 2023, Winston delivered a victory for Corning in a decade-long dispute over cell-culturing technology. Following a bench trial in November 2022 and extensive post-trial briefing and argument, a Minnesota federal court found in favour of Corning. Following that win, Winston represented Corning in the appeal of that matter as well as another patent infringement case between the parties.

The second case is a patent-infringement declaratory judgment action involving patents other than those at issue in the first case. The case proceeded through fact and expert discovery. On October 23, 2023, the court granted Corning summary judgment of noninfringement of two of the three asserted patents.

Following an appellate oral argument in the first case on February 6, 2025, and an appellate win for Corning days later, the parties and several third parties reached a favourable resolution on all remaining issues in the patent infringement case, and the case was dismissed.

The team is George Lombardi; Ivan Poullaos; Kimball Anderson; and Michael Meneghin.

• Xockets v NVIDIA et al

Winston is defending Microsoft in a complex antitrust and patent litigation involving artificial intelligence (AI). Plaintiff Xockets asserts that NVIDIA and Microsoft infringe its patents through the use of NVIDIA data processing units (DPUs), which are used for creating and training AI systems. Xockets further alleges that NVIDIA, Microsoft, and RPX engaged in anticompetitive practices with respect to licensing of its patents.

Defendants have opposed Xockets’ motion for preliminary injunction, which remains pending before the court, and have filed motions to dismiss the antitrust claims. Winston’s Jeffrey Kessler argued against the preliminary injunction on behalf of Microsoft in October 2024. The court has not yet issued a decision.

Winston has filed a motion to sever and stay under the customer-suit exception on behalf of Microsoft, which is fully briefed and awaiting a decision from the Court.  Defendants have also moved to transfer the case to the Northern District of California, which is fully briefed and awaiting a decision from the Court. The Court has stayed all other case activity pending the motion to transfer.

Winston’s team is Kelly Hunsaker; Jeffrey Kessler; Aldo Badini; Matthew McCullough; Lauren Duxstad; Daniel Marzagalli; Becca Ou; and Samuel Riebe.

Clients:

Abbott Laboratories, Advanced Micro Devices (AMD), Alphatec, Cisco Systems, Comcast, Corning, Hikma Pharmaceuticals, HP, Microsoft, MSN Laboratories, PayPal, Snap, Sun Pharmaceutical Industries, Teva North America, US Well Services