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Kathleen Gersh’s practice focuses on intellectual property law, with emphasis on Hatch-Waxman litigation and counseling. She has significant experience managing complex pharmaceutical litigations, including coordinating litigation teams across multiple jurisdictions. She has been involved in all phases of ANDA litigation, with patents covering compounds, formulations, dosing regimens and methods of treatment.

She has broad experience helping life sciences clients protect their innovations, including providing strategic counseling to develop and maximize patent and regulatory exclusivities for pharmaceutical and biologic products, conducting pre-suit investigations, engaging in inter partes review proceedings, and doing prosecution and opinion work (infringement, validity, freedom to operate). 

Kathleen further relies on her litigation experience to help clients safeguard and monetize their intellectual property (IP) through comprehensive licensing agreements with co-marketing and co-distribution partners. She is a Certified Licensing Professional.

Litigators have the benefit of hindsight: The facts are what they are, and that’s what you work with. Transactional work, on the other hand, makes you look into the future like a clairvoyant to protect your client from potentially negative events. I love having both sides as part of my practice.

She has worked with clients of all sizes on both inbound and outbound transactions, including strategic collaboration and partnering arrangements, as well as research, development and commercial relationships (such as manufacturing, supply, distribution and service agreements). Kathleen has provided advice and diligence on IP and its role in mergers, acquisitions, funding transactions and joint ventures. 

Prior to entering private practice, she worked as a lawyer for NeXstar Pharmaceuticals, gaining in-house experience and perspective that she draws upon to help accomplish her clients’ business objectives. 

In addition to her client work, Kathleen serves as co-chair of Loeb & Loeb’s Women’s Affinity Group, whose mission is to create a more inclusive culture, enrich the work environment, and identify solutions and strategies that help the firm recruit, develop, advance and retain talented female lawyers. She also serves as a member of the Global Advisory Board of Women in Law Empowerment Forum, an organization focused on providing networking and professional development opportunities to women working in law firms and corporate law departments. She is also active with the parents’ association at her children’s school, serving in both leadership and nonleadership roles.


  • University of New Hampshire School of Law (formerly Franklin Pierce Law Center), J.D.
  • University of New Hampshire School of Law (formerly Franklin Pierce Law Center), Master of Intellectual Property
  • University of Texas at Austin, B.S., Chemistry

Court Admissions

  • U.S. Court of Appeals, Federal Circuit
  • U.S. District Court for the Southern District of New York
  • U.S. Supreme Court

Bar Admissions

  • New York
  • United States Patent and Trademark Office


  • Member, Federal Circuit Bar Association
  • Member, Intellectual Property Owners Association
  • Member, New York Intellectual Property Law Association
  • Member, American Intellectual Property Law Association