AFS Law

ArentFox Schiff LLP is a prominent full-service law firm with headquarters in Washington, D.C., and a substantial office footprint across major U.S. cities including New York City, Boston, Chicago, Los Angeles, and San Francisco. With over 650 lawyers and policy professionals, the firm operates as a large, diversified legal entity, recognized among the top firms in the U.S.; it was ranked #80 in the 2027 Vault Law 100. Chambers USA also recognizes 68 of its attorneys and 25 practice areas in its 2026 rankings, including its Intellectual Property practice in Illinois, where it holds a Band 3 ranking.

The firm's intellectual property litigation practice maintains a strong focus on complex patent disputes across a diverse range of technology sectors. ArentFox Schiff is particularly adept in industries such as pharmaceuticals and life sciences, telecommunications, consumer electronics, software, semiconductors, and medical devices. Their expertise includes complex Hatch-Waxman and biosimilars litigation, advising clients on the Biologics Price Competition and Innovation Act (BPCIA), and managing intellectual property disputes at the International Trade Commission (ITC).

Based on tracked appearances, ArentFox Schiff primarily works on the plaintiff side in patent litigation, with one recorded instance. [cite: TRACKED_CASES] However, the firm is notably recognized for representing generic pharmaceutical manufacturers in Abbreviated New Drug Application (ANDA) litigation, which often involves challenging originator drug patents. This role positions them frequently as advocates for market challengers in the life sciences sector.

A notable case handled by the firm is Fresenius Kabi SwissBioSim GmbH v. Regeneron Pharmaceuticals, Inc., where ArentFox Schiff represented Fresenius Kabi. In this matter, Fresenius Kabi filed inter partes review (IPR) petitions against Regeneron's U.S. patents related to aflibercept (Eylea®). While the Patent Trial and Appeal Board (PTAB) denied institution of these IPRs, the dispute ultimately resulted in a settlement in February 2026, allowing Fresenius Kabi to launch its biosimilar aflibercept at an undisclosed future date. The firm has also secured summary judgment of non-infringement for a pharmaceutical client in a chemotherapy drug patent case and a patent win for cannabis brand STIIIZY in a U.S. Customs and Border Protection Rule 177 proceeding.

ArentFox Schiff actively engages in post-grant proceedings before the PTAB, including inter partes reviews (IPR), post-grant reviews (PGR), reexaminations, interferences, and trademark oppositions and cancellations. Key partners in the firm's IP litigation practice include Sailesh Patel, who co-chairs the Intellectual Property Litigation practice and the Life Sciences Industry Group, with over 25 years of experience in Hatch-Waxman and biosimilars litigation. Other prominent patent litigation partners include Imron T. Aly, highly regarded for his Hatch-Waxman and biosimilars expertise, and Christopher Schultz and Howard J. Susser, both seasoned trial attorneys with extensive experience litigating patent cases in various forums, including the PTAB and Federal Circuit.