Thomas J. Engellenner

Thomas J. Engellenner


Boston, MA
Phone: 617.204.5189    Fax: 617.204.5150

"Highly respected." — Chambers USA 2016

Thomas J. Engellenner is a partner in the Intellectual Property Department of Pepper Hamilton LLP, resident in the Boston office. Mr. Engellenner’s practice includes patents, licensing, trademarks, copyrights and litigation. He has particular expertise in the fields of biotechnology, pharmaceuticals, analytical instruments and medical devices.

Mr. Engellenner has more than 30 years of experience in prosecuting and litigating patents and advising clients generally on intellectual property strategies. His litigation experience includes patent infringement cases in the U.S. federal courts, and interference and reexamination proceedings at the U.S. Patent Office, as well as infringement and validity trials in Japan and Europe.

Most recently, Mr. Engellenner’s practice has expanded to include post‑grant proceedings at the U.S. Patent Office, which were established in 2012 by the America Invests Act. He is currently counsel in over 40 inter partes review proceedings, involving 15 different patents. He also is a founder and editor of a leading blog on this topic:

Prior to joining Pepper, Mr. Engellenner was a partner with Nutter McClennen & Fish LLP in Boston, where he was chair of the firm’s Life Sciences Practice Group and co-chair of the firm’s Patent Practice Group.

Mr. Engellenner began his career as a trial attorney for the U.S. Environmental Protection Agency. Prior to entering private practice, he worked for the Massachusetts Institute of Technology as a patent and licensing attorney in the Office of Technology Licensing. Since entering private practice, Mr. Engellenner has obtained over one hundred patents for MIT.


  • J.D., Boston University School of Law
  • M.S., Environmental Studies, Rensselaer Polytechnic Institute
  • B.S., Engineering, Rensselaer Polytechnic Institute

Bar Admissions

  • U.S. Patent and Trademark Office
  • Massachusetts
  • New York

Court Admissions

  • U.S. Court of Appeals, Federal Circuit
  • U.S. District Court, District of Massachusetts

Practice Areas

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