David K. Barr concentrates in the areas of patent, trade secret, and unfair competition litigation and counseling. Mr. Barr's experience includes litigation in federal and state courts, appeals to the Federal Circuit Court of Appeals and practice before the US Patent and Trademark Office, including contentious inter partes proceedings. Mr. Barr has been lead trial counsel in many complex Hatch-Waxman and biotech patent infringement cases, and has counseled clients on product development and strategic patent planning. He has extensive experience in intellectual property transactions, including licenses and acquisitions. Mr. Barr has also conducted numerous patent due diligence investigations, and has drafted patent license and related agreements. His patent matters have involved a variety of technologies, including biotechnology, pharmaceuticals, industrial chemistry and biomedical and mechanical devices.

Mr. Barr has authored articles and has lectured on a variety of intellectual property issues. He is a co-author and co-editor of the treatise Pharmaceutical and Biotech Patent Law (Practising Law Institute, 2016).

Mr. Barr received his law degree from the George Washington University Law School, where he was an Associate Editor of the George Washington Journal of International Law and Economics.


  • Amgen v. Sanofi/Regeneron. Represented Sanofi and Regeneron in successfully invalidating Amgen's patents directed to PCSK9 antibodies after a jury trial in the District of Delaware, preserving Sanofi and Regeneron's ability to continue to market its life-saving cholesterol-reducing drug Praluent®. The district court judgment in favor of our clients Sanofi and Regeneron was unanimously affirmed by the Court of Appeals for the Federal Circuit.
  • Hologic and Grifols in securing a complete jury verdict in defending against a $90-million patent claim brought by medical diagnostics company bioMerieux involving HIV-1 detection technology.
  • Novartis in patent litigation relating to Chimeric Antigen Receptor modified T cells used for the treatment of leukemia. Trustees of the University of Pennsylvania and Novartis Pharmaceuticals Corporation v. St. Jude Children's Research Hospital, Inc. and Juno Therapeutics, Inc. (E.D.Pa.).
  • Novartis in multiple Hatch-Waxman actions directed to Novartis' Gleevec® drug product. Sun Pharma Global FZE v. Novartis Pharmaceuticals Corp. and Novartis AG (D.N.J.); Novartis Pharmaceuticals Corp. and Novartis AG v. Amneal Pharmaceuticals, Natco Pharma Ltd., and Roxane Laboratories, Inc.
  • Novartis in successfully defending against an antitrust claim based on alleged sham patent litigation and Walker Process fraud stemming from the settlement of Hatch-Waxman litigations relating to Gleevec®. The action was dismissed by the District of Massachusetts, which was unanimously affirmed by the First Circuit Court of Appeals.
  • Sanofi-aventis in patent infringement litigation against ten drug companies seeking to market generic versions of the company's Allegra® antihistamine products. Lead trial counsel for Sanofi-aventis in seven-day bench trial against Dr. Reddy's. Aventis Pharmaceuticals, Inc. v. Dr. Reddy's Laboratories, Ltd. et al. (D.N.J.)
  • GlaxoSmithKline and Stiefel in defending two patent infringement actions relating to Stiefel's Veltin™ dermatologic product. Medicis, et al. v. Stiefel Labs (W.D. Tex.); Medicis, et al. v. Stiefel and GlaxoSmithKline (D.N.J.)
  • Vivelle Ventures, Noven Pharmaceuticals, and Novartis in Hatch-Waxman patent litigation regarding the transdermal estradiol drug product, Vivelle Dot®; Vivelle Ventures, Noven Pharmaceuticals and Novartis v. Mylan Technologies, et al. (S.D.N.Y.).
  • Seattle Children's Hospital and Novartis in Hatch-Waxman patent litigation regarding TOBI®, an inhalable antibiotic formulation for treatment of cystic fibrosis patients. Seattle Children's Hospital and Novartis v. Teva Pharmaceuticals (D. Del.).
  • Novartis in Hatch-Waxman patent litigation against three generic drug companies seeking approval to market generic versions of Novartis' urinary incontinence drug, Enablex®. Novartis v. Teva Pharmaceuticals, Watson Pharmaceuticals and Anchen Pharmaceuticals (D. Del.).
  • Chiron in its successful assertion of its patents covering nucleic acid methods and probes for detecting the presence of the Hepatitis C virus (HCV). Three-year litigation resulted in consent judgment that Chiron's patents were valid, enforceable, and infringed by Roche, and that Bradley breached a prior contract with Chiron. Chiron Corporation v. F. Hoffmann-LaRoche Ltd. and Bradley (N.D. Cal.).
  • Rockefeller University and Chiron in litigation asserting infringement of Rockefeller's patents relating to antibodies to Tumor Necrosis Factor (TNF) against manufacturers of Remicade® and Humira®, used to treat rheumatoid arthritis. Rockefeller University and Chiron Corporation v. Centocor, Inc. and Abbott Laboratories (E.D. Tex.).
  • DuPont Merck and ImaRx in successfully briefing and arguing motions to dismiss, on personal and subject matter jurisdiction grounds, plaintiff's complaint, which sought to institute an interfering patents action among several owners of patents directed to ultrasound contrast agents. Mallinckrodt Medical, Inc. v. DuPont Merck Pharmaceutical Corp. and ImaRx Pharmaceutical Corp., 989 F. Supp. 265 (D.D.C. 1998).
  • Marion Merrell Dow (MMD) in patent infringement action against drug company seeking to market a generic version of MMD's non-sedating antihistamine Seldane®. Marion Merrell Dow Inc. v. Baker Norton Pharmaceuticals Inc. (S.D. Fla.).
  • Bayer in patent infringement litigation against drug company seeking to market a generic version of Bayer's leading antibiotic, Cipro®. Case settled prior to trial. Bayer A.G. v. Barr Laboratories (S.D.N.Y.).



IAM Patent 1000
Litigation (New York) (2013-2021)
The Legal 500 US
Patent Litigation: Full Coverage (2021)
Managing Intellectual Property
"IP Star" (New York) (2013-2021)


  • JD, The George Washington University Law School, 1983, with honors
  • BS, Biological Sciences, Cornell University, 1980
  • New York
  • District of Columbia
  • US Patent and Trademark Office
  • US Court of Appeals for the Federal Circuit
  • US District Court, Eastern District of New York
  • US District Court, Southern District of New York
  • Member, American Bar Association
  • Member, New York State Bar Association
  • Member, Federal Circuit Bar Association

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