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Aaron Stiefel

Aaron Stiefel

Co-chair, Intellectual Property Department

New York
T: +1 212 836 8442
F: +1 212 836 8689

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  • Harvard Law School
    JD, cum laude, 1981
  • Yeshiva University
    MA, Chemistry, 1978
  • Yeshiva University
    BA, 1978

Bar Admission(s)

  • New York
  • New Jersey
  • US Court of Appeals for the Second, Third, District of Columbia and Federal Circuits
  • US District Courts for the Southern and Eastern Districts of New York, the Northern District of California and the District of New Jersey

Aaron Stiefel, co-chair of the Intellectual Property Department, has represented leading research-based pharmaceutical and biotechnology companies, such as Pfizer Inc. and Novartis, in all aspects of complex patent litigations. His experience includes bringing and defending patent infringement actions concerning antibiotics, antihypertensives, antifungal medications, treatments for erectile dysfunction, the cloning of alpha-interferon, testing of blood for hepatitis C infection, monoclonal antibodies, contact lenses, surgical devices, methods for producing transgenic mice, smartphone apps and data storage products. Mr. Stiefel frequently represents research-based companies in litigation against generic drug manufacturers under the Hatch-Waxman Act. He has counseled clients with respect to a host of patent law issues and has authored articles and lectured on patent law. Mr. Stiefel has also represented pharmaceutical companies regarding false advertising and unfair competition claims.

Mr. Stiefel is widely recognized for his work in the IP space. He was recently named an “IP Star” by Managing IP Handbook 2016, recommended by The Legal 500 United States 2016 and ranked in IAM Patent 1000 2016 for his work in patent litigation. The following quote from 2016’s IAM 1000 says it all: “Aaron Stiefel and Daniel DiNapoli are two of the best pharmaceutical patent litigators anywhere in the world. They have an excellent track record and are people you can trust with your biggest cases and most valuable assets. The technical and legal services they provide are top notch.”

Mr. Stiefel has also handled a vast array of commercial litigation matters, at both the trial and appellate levels, in state and federal courts and in arbitration. His litigation experience includes cases involving inter alia, breach of contract and breach of fiduciary duty claims, product liability claims, alleged violations of the securities laws, bankruptcy claims, and claims regarding real property taxes.

Mr. Stiefel has handled jury trials, bench trials, Markman hearings and arbitrations, and has argued before both federal and state appellate courts and trial courts. He also spent time as trial counsel in the office of the New York City Corporation Counsel. Mr. Stiefel is a member of the American Bar Association, the New York State Bar Association and the Federal Circuit Bar Association.

Representative Matters

  • Pfizer as lead counsel in a patent infringement case against Teva. Successfully preserved Pfizer’s market exclusivity for its blockbuster drug Viagra®, defeating a challenge by Teva Pharmaceuticals USA Inc., which sought FDA approval to sell a generic version of the drug. The court rejected Teva’s assertions that the patent is invalid as having been obvious and unenforceable under the doctrine of inequitable conduct. Pfizer Inc. et al. v. Teva Pharmaceuticals USA, Inc. et al., 2:10-cv-128 (E.D. Va.)
  • Pfizer as lead counsel in a patent infringement case against Apotex, Lupin, Mylan, Teva and Watson, involving Pfizer’s blockbuster drug Celebrex®. Pfizer Inc. v. Lupin Pharma et al., 2:13-cv-121 (E.D. Va.)
  • Pfizer as lead counsel in patent infringement cases against generic drug manufacturers Actavis, Apotex and Mylan, based on each defendant’s filing of an ANDA seeking FDA approval for generic versions of Viagra®. Pfizer Inc. v. Actavis, Inc. et al., 1:10-cv-08197-TPG, (S.D.N.Y.)
  • Cephalon as lead counsel in patent infringement litigation against ANDA-filer seeking FDA approval to market generic version of Cephalon’s Treanda® injection product. Cephalon Inc. v. Fresenius Kabi USA, LLC, 1:15-cv-oo536-LPS (D. Del.)
  • Acorda Therapeutics in a set of patent infringement cases against eight generic drug manufacturers involving Ampyra® (dalfampridine), an oral medication to improve walking in people with multiple sclerosis (MS). Acorda Therapeutics Inc. v. Actavis et al., 1:14-cv-00882-LPS (D. Del.)
  • Pfizer in defense of a patent infringement case brought by Apotex related to Pfizer’s Accupril® Apotex v. Pfizer Inc., 0:12-cv-60704 (S.D. Fl.)