• New Jersey
  • New York
  • Pennsylvania
  • U.S. Patent and Trademark Office


  • American Chemical Society
  • American Intellectual Property Law Association
  • New York Intellectual Property Law Association


  • Fordham University School of Law, JD
  • New York University, MS
  • Columbia University, BS
Download V-Card

Jay P. Lessler


New York, NY v. +1.212.885.5176 f. +1.917.332.3773

Mr. Lessler concentrates his practice in domestic and foreign patent procurement, client counseling and patent litigation, primarily in the chemical, pharmaceutical, and computer software arts.

Working closely with inventors and in-house counsel, Mr. Lessler devises effective strategies to build and protect intellectual property assets, from initial drafting of patent applications to post-grant proceedings. His experience includes:

  • reissue
  • reexamination and patent term extension proceedings
  • domestic and foreign patent portfolios
  • conducting due diligence investigations and validity and freedom-to-operate studies
  • counseling clients in connection with the Hatch-Waxman Act and the Biologics Price Competition and Innovation Act 
  • preparation of Paragraph IV Notice letters and Offers for Confidential Access pursuant to the Hatch-Waxman Act

Mr. Lessler also has significant ANDA and biotech litigation experience.  His recent representations include:

  • Ascio Pharmaceuticals, Inc. v. Three Rivers Pharmaceuticals, LLC (D. Ga., Civ. No. 1:10-cv-1583)
  • Schering Corp., et al. v. Glenmark Pharmaceuticals, Inc. USA, et al. (D.N.J., Civ. No. 2:07-cv-01334)

Mr. Lessler has been the co-chair of Practising Law Institute’s (PLI’s) annual Advanced Patent Prosecution Workshop since 2006.  He was also a speaker at PLI’s Patent Boot Camp Workshop from 2002 to 2006.

Mr. Lessler has co-authored numerous chapters on Patent Law and the Hatch-Waxman Act, including the “Generic Drug-Approval Process: Hatch-Waxman Update” chapter in The Pharmaceutical Regulatory Process, Second Edition (edited by I. Berry) (2008), and the "Non-Obviousness, Regulatory Exclusivities for Pharmaceutical Products, Post-Grant Procedures," and "How to Prosecute a Biopharma Patent Application" chapters in Biotechnology And Pharmaceutical Patents (2007) (Aspen).

He has also presented talks on various areas of patent law, including at the New York Intellectual Property Law Association’s 2011 Fall Patent CLE (November 2011) (“Challenging the Validity of Patent”), the Houston Intellectual Property Law Association (September 2011) (“Can You Patent That? Recent Developments in Patentable Subject Matter”), the New York Intellectual Property Law Association’s 26th Annual Joint Patent Practice Seminar (April 2010) (“What is “Material Changed” under 35 U.S.C. §271(g)? Amgen v. Hoffmann-La Roche, 580 F.3d 1380 (Fed. Cir. 2009)”) and the Controlled Release Society (CRS) Annual Meeting, Young Scientist Workshop, “Intellectual Property” (Copenhagen, Summer 2009).