Lawyer Profile
Eileen M. McMahon
Toronto, Ontario

Overview
Working with entrepreneurs and innovators for over 30 years, Eileen is Chair of Torys’ Intellectual Property and Food and Drug Regulatory practices. She advises Fortune 500 companies, leading manufacturers and innovators, as well as small- and medium-sized enterprises, on complex intellectual property and regulatory issues. She is recognized as Canada’s leading life sciences lawyer, with deep market insight and a practical, business-minded approach.
Eileen is a co-founder of the intellectual property and food and drug regulatory practices at Torys. She represents the entire spectrum of companies on regulatory clearance and intellectual property protection of products. Across sectors—including life sciences (pharmaceuticals, medical devices, natural health products), agribusiness, consumer products and more—Eileen helps clients identify, protect and leverage IP and regulatory assets, obtain and maintain market exclusivity, handle high-risk situations (corrective actions, recalls, regulatory orders), and navigate the impact of current and proposed laws on clients’ ability to sell products. Eileen also has market-leading experience with patented medicines and oversight of Canada’s Patented Medicines Prices Review Board (PMPRB). Eileen also represents investors and companies looking to finance or invest in companies with intellectual property and regulatory assets, as well as companies looking to acquire or divest such assets.
Eileen’s unique experience and strong market presence are well recognized: in addition to her Band 1 ranking in Intellectual Property by Chambers & Partners, Eileen is the only Canadian lawyer to be recognized as a Star Individual in Life Sciences. Managing IP regards her as one of the world’s top 250 women in IP, and The Legal 500 recognizes her as one of Canada’s leading lawyers in intellectual property. Eileen was recently recognized as a “Hall of Fame Lawyer” for receiving “constant praise from her clients for continued excellence” and identified as being “at the pinnacle of the profession”, in the 2024 edition of The Legal 500 Canada. Best Lawyers in Canada also recognized Eileen as Lawyer of the Year in Biotechnology and Life Science for 2024.
Eileen is a registered patent and trademark agent in the United States and Canada. She is also a Certified Licensing Professional of the Licensing Executive Society (LES).
Eileen is very knowledgeable and comes informed to every discussion with a strategy in mind.’
Eileen is on the Advisory Board of the Food and Drug Law Institute’s 2022 Food and Drug Law Journal Editorial and the Advisory Board of Canadian Women in Life Sciences. She is also a member of the Intellectual Property Institute of Canada and the Intellectual Property Owners Association (Pharmaceutical & Biotechnology Issues Committee).
In terms of community and volunteer involvement, Eileen is a Trustee of the Board of The Centre for Addiction and Mental Health (CAMH) and Chairs its Research Committee. Previously, Eileen was a director of the National Cycling Institute of Milton (Milton Velodrome), The Credit Valley Hospital and a founding officer and director of TOHealth and of the Canadian Healthcare Licensing Association.
As one of Canada’s Top 100 Most Powerful Women (Women's Executive Network), Eileen participates in various mentoring programs for women.
Practice Areas
Bar Information
Called to the bar: 1987 (ON)