• Admitted to the Bar of Ontario in 1976
  • Registered Canadian Patent and Trademark Agent
  • Registered U.S. Patent and Trademark Agent
  • LL.B., University of Toronto
  • B.A.Sc., Chemical Engineering, University of Waterloo
Doug Deeth is a founding member and the managing partner of the firm. He practises exclusively in the areas of intellectual property and technology law, concentrating on litigation and licensing matters.

Practice Areas

Doug has been recognized in several international reviews as one of Canada’s leading intellectual property lawyers. His practice combines his extensive litigation experience with an expertise in drafting and negotiating license and product development agreements. He provides timely, practical and pragmatic advice to clients on the clearance, protection and enforcement of all forms of technology and intellectual property rights, and has particular expertise in chemical and pharmaceutical products and processes.

Doug has more than thirty years of litigation experience, ranging from the most complex and sophisticated intellectual property litigation to judicial review proceedings and interlocutory injunction applications. He appears regularly before the Federal Court of Canada and the courts of the Province of Ontario.


2024 LEXPERT-ranked Lawyer

  • Canadian Legal Lexpert Directory, Consistently Recommended for Intellectual Property, 2024
  • Best Lawyers in Canada, Intellectual Property 
  • Canadian Legal Lexpert Directory, Most Frequently Recommended for Intellectual Property
  • Chambers and Partners Canada Guide, Band 3 - Intellectual Property Litigation Lawyers
  • Chambers and Partners Global Guide, Band 3 - Intellectual Property Litigation Lawyers in Canada
  • IAM Patent 1000: The World's Leading Patent Professionals, Patent Litigation in Canada
  • Lexpert / American Lawyer Guide to the Leading 500 Lawyers in Canada (ALM 500), Intellectual Property
  • Who's Who Legal, Global Leader and National Leader in Life Sciences for Patent Litigation
  • Who's Who Legal, Global Leader and National Leader in Patents

Professional Affiliations

  • International Federation of Intellectual Property Attorneys (FICPI), Past President of FICPI International
  • International Federation of Intellectual Property Attorneys (FICPI), Former President of Communications Commission
  • International Federation of Intellectual Property Attorneys (FICPI), Past President of FICPI Canada
  • American Bar Association (ABA), Member
  • American Intellectual Property Law Association (AIPLA), Member
  • International Association for the Protection of Intellectual Property (AIPPI), Member
  • Canadian Bar Association (CBA), Past President of Intellectual Property Section
  • Ontario Bar Association (OBA), Member
  • International Trademark Association (INTA), Member
  • Intellectual Property Institute of Canada (IPIC), Member
  • Intellectual Property Owners (IPO), Member
  • Canadian IT Law Association (IT.CAN), Member
  • Toronto Lawyers Association (TLA), Member
  • Professional Engineers of Ontario (PEO), Member
  • The Lawyers Club, Member


November 21, 2022

The Unified Patent Court (UPC) will be a court common to seventeen EU Member States; any of the remaining EU Member States may accede to the jurisdiction of the UPC Agreement at any time. The UPC is intended to offer a uniform, specialised, and efficient framework for patent litigation at a European level, hearing both infringement and revocation actions. 

May 11, 2017

A number of the partners attended the CBA IP Section's annual Judges' Dinner, which allows the bar to mingle with the bench at a black tie event in Ottawa.  

For more about the CBA IP Section, see http://www.cba.org/CBA/sections_IP/main/.