Andrew D. Cohen, Ph.D., a trained organic chemist, is a Partner in Patterson Belknap's Litigation department. He is an accomplished patent litigator, with over 15 years of experience in patent law. Dr. Cohen focuses his practice on life science patent litigation, where he leverages his scientific background to translate complicated technology into easy-to-understand terms.  He has represented innovators in Hatch-Waxman and Biologics Price Competition and Innovation Act (BPCIA) cases, and has represented clients in inter partes reviews (IPR) proceedings before the patent office.  A well-rounded litigator, Dr. Cohen also represents clients in complex commercial disputes (including arbitrations) and defending consumer class actions.  He maintains an active pro bono practice in areas of civil rights, immigration, and housing.  Dr. Cohen has also helped lead the firm’s long-standing collaboration with Legal Services of the Hudson Valley, representing low-income tenants in housing disputes in Westchester County and surrounding regions.

Prior to joining the firm, Dr. Cohen served as a law clerk to the Hon. Cathy Seibel of the United States District Court for the Southern District of New York. Prior to clerking, Dr. Cohen also spent three years as a patent agent at an international law firm, where he worked on motion practice, patent prosecution, due diligence, and opinion drafting. Before that, he was a scientific advisor for three years at a boutique intellectual property law firm, where he worked on Hatch-Waxman litigations, as well as due diligence, opinion drafting and patent prosecution.

In December 2024, Dr. Cohen was featured in The American Lawyer’s “Litigator of the Week” column for successfully defending the validity of the patent of a blockbuster medication on behalf of a Fortune 100 pharmaceutical company. He was recognized as a Rising Star in the New York-Metro edition of Super Lawyers from 2017-2020.

In 2024, Dr. Cohen was appointed to the Board of Trustees for Burke Rehabilitation Hospital.

Representative Experience:

  • Obtained a trial victory, affirmed on appeal, for a Fortune 100 pharmaceutical company in a Hatch-Waxman patent litigation following a multi-week virtual bench trial. At stake was nearly 10 years of patent protection for a blockbuster medicine with over $1.5 billion in annual sales in the United States.
  • Obtained a trial victory, affirmed on appeal, for a Fortune 100 pharmaceutical company in a Hatch-Waxman patent litigation involving a dosing regimen for patients who had missed a dose of a long-acting injectable antipsychotic medicine.
  • Representing a Fortune 100 pharmaceutical company in a Hatch-Waxman patent litigation involving an intranasal depression product.
  • Represented a Fortune 500 biotechnology company in obtaining dismissal of a $530 million patent infringement suit regarding recombinant DNA expression vectors.
  • Represented a multinational pharmaceutical company in one the first cases brought under the BPCIA involving a blockbuster antibody product and methods of manufacturing biologics.
  • Represented multinational pharmaceutical company against U.S. Customs in a bench trial, successfully obtaining judgment that the company’s blockbuster small-molecule drug can be imported duty-free.
  • Represented a pharmaceutical company in arbitration regarding small-molecule product royalties.

  • U.S. Supreme Court
  • U.S. Patent and Trademark Office
  • U.S. Court of Appeals, Federal Circuit
  • U.S. District Court, Southern District of New York
  • U.S. Court of International Trade
  • New York

MEMBERSHIPS: Burke Rehabilitation Hospital (Member of the Board of Trustees); American Chemical Society; New York City Bar Association (Member of the Patents Committee); New York Intellectual Property Law Association (Member of the Amicus Briefs Committee).

SPEAKING ENGAGEMENTS: Panelist, "Promise and Peril for Patents: Navigating Mandated Disclosures and Prior Art Pitfalls," ACI's 2026 Paragraph IV Disputes Conference (April 22, 2026); Roundtable Host, "Patenting and Patentability During Clinical Development," Kisaco Research's 2025 Pharma & Biotech Patent Litigation North America Conference (November 18, 2025); Panelist, "Section viii Carveouts and Inducement Analysis: Post Launch Considerations Following Amarin v. Hikma," ACI Paragraph IV Disputes Conference (April 30, 2025); Panelist, "In re Cellect: Understanding the Implications for Obviousness-Type Double Patenting and Patent Type Term Adjustments," ACI Paragraph IV Disputes Conference (April 26, 2024); Panelist, "Preparing for Parallel Proceedings: Maneuvering through the District Court and Inter Partes Review," ACI Paragraph IV Disputes Conference (April 19, 2023)

RECOGNITIONS: Featured in The American Lawyer’s “Litigator of the Week” column (2024); Recognized for pro bono work in Legal Services of the Hudson Valley’s Pro Bono Week (2024); Recognized as a “Rising Star” in the New York-Metro edition of Super Lawyers (2017-2020)

  • Fordham University School of Law (J.D., magna cum laude, 2012)
    • Order of the Coif
    • Senior Articles Editor, Fordham Law Review, Vol. 79
    • Wilkinson Scholar
  • Johns Hopkins University (Ph.D., 2006)
    • Chemistry (Organic)
  • Johns Hopkins University (M.A., 2004)
    • Chemistry (Organic)
  • Princeton University (A.B., cum laude, 2000)
    • Chemistry (Organic)