Monica Biringer - Corporate Tax Lawyer in Toronto

Monica Biringer

Partner and Co-Chair, Taxation

Key Contact: Taxation

Key Contact: Tax Controversy & Litigation

Contact Information

tel: 416.862.6830



Bar Admission

Ontario, 1986


  • University of Toronto, LL.B./B.C.L.
  • Queen’s University, B.A.



Monica is Co-Chair of Osler’s National Tax Group (alongside with Patrick Marley). Her practice includes all aspects of corporate income tax with an emphasis on tax controversy.

Monica has extensive experience in cross-border mergers, inbound corporate financing and acquisitions, leasing as a form of financing and financial restructuring. At present, Monica’s practice focus is on tax litigation matters. Monica was co-counsel on the first case involving the general anti- avoidance rule to reach the Supreme Court of Canada and the first case under the provincial general anti-avoidance rule in Ontario, Alberta and British Columbia.

Monica is an author and speaker at conferences on various Canadian tax matters, and is a past Governor of the Canadian Tax Foundation, has taught at the Bar Admission Course and is on the editorial board for the Federated Press, a Corporate Finance periodical. Prior to joining Osler, she worked in the International Tax Office of Chuo Coopers & Lybrand in Tokyo.

Monica is continuously ranked as a leader in tax law by International Tax Review, Lexpert Guide to Leading 500 Lawyers in Canada and Best Lawyers in Canada, Who’s Who Legal, Chambers Global and Women in Business Law.

Monica was recognized as "Tax Dispute Resolution Lawyer of the Year" by the 2020 Euromoney LMG Americas Women in Business Law Awards, received the 2018 H.J Crawford Award in recognition for her volunteer support of University of Toronto Schools (UTS) over the course of four decades, including capital campaign leadership, and was also a 2017 Lexpert Zenith Award recipient for her exceptional leadership skills and accomplishments in supporting the advancement of women in the legal profession.

    • Cameco Corporation in its successful dismissal of CRA appeal by the Supreme Court of Canada
    • J.D. Irving Limited in its successful appeal of Revenu Québec’s reassessments
    • Veracity in its appeal under the B.C. General Anti-Avoidance Rule to the B.C. Court of Appeal
    • Target in connection with the wind-down of its Canadian operations under the Companies’ Creditors Arrangement Act
    • London Stock Exchange in its proposed merger with the Toronto Stock Exchange
    • Target Canada Co. in its acquisition of leases from Zellers Inc.
    • IBM in its acquisition of Cognos Inc; Clarity Systems, Platform Computing Inc., and Varicent Software Inc.
    • Precision Drilling Inc. in its financing structure appeal under the Ontario General Anti-Avoidance Rule to the Ontario Court of Appeal
    • Husky Energy Inc. in its financing structure appeal under the Alberta General Anti-Avoidance Rule to the Alberta Court of Appeal
    • Canada Trustco in its tax appeal under the Federal General Anti-Avoidance Rule to the Supreme Court of Canada
    • Canadian Association of Petroleum Producers in its intervention in the tax appeal by Daishowa to the Supreme Court of Canada
    • AT&T Canada (previously MetroNet) in its plan of arrangement with AT&T Corp. and restructuring under the CCAA
    • Seagram in its merger with Vivendi Universal and Vivendi Universal/Seagram in its sale of the spirits business to Diageo/Pernod Ricard
    • Newbridge in its merger with Alcatel

  • Chambers Canada: Canada’s Leading Business Lawyer: Recognized in Tax; Tax: Litigation
  • Chambers Global: The World's Leading Business Lawyers: Recognized in Tax
    • "...[Monica] advises clients on corporate taxation issues, with a focus on M&A and finance. She continues to advise on the winding-down of Target's Canadian operations."
  • The Canadian Legal Lexpert Directory: Recognized in Litigation - Corporate Tax; Corporate Tax
  • The Lexpert/American Lawyer Guide to the Leading 500 Lawyers in Canada: Recognized in Corporate Tax
  • The Lexpert Guide to the Leading US/Canada Cross-Border Corporate Lawyers in Canada: Recognized in Litigation - Corporate Tax; Corporate Tax
  • Lexpert Zenith Awards: Celebrating Women in Law: Recognized as a Winner
  • The Legal 500: Recognized as a Recommended Lawyer, Tax Law
  • Best Lawyers in Canada: Recognized in Tax Law
  • Who’s Who Legal: Thought Leaders Global Elite 2021: Recognized in Corporate Tax - Controversy
  • International Tax Review: Recognized in Tax Controversy; Women in Tax; Highly Regarded Lawyer; Tax Leader
  • International Financial Law Review: Shortlisted for Best in Tax Dispute Resolution in Business Law Awards 2020
  • Euromoney LMG Americas Women in Business Law Awards: Recognized as "Tax Dispute Resolution Lawyer of the Year" 2020

  • UTS Co-Chair Capital Campaign (2016 - present).
  • UTS Foundation, Director and Fundraiser (2006 to 2008 and 2010 to 2012).
  • Hospital for Sick Kids, Fundraiser (2006 to 2012).

  • Canadian Bar Association
  • Law Society of Ontario
  • Canada Finance and Leasing Association, Tax Section

  • The GAAR and its application to the Loss Streaming Rules - Corporate Finance, Federated Press, Volume XXII, No.2 (2019)
  • Univar and Subsection 212.1(4): The Significant Impact of a Subsequent Legislative Amendment on the Application of the GAAR (Monica Biringer and Taylor Cao) - Corporate Finance, Federated Press, Volume XX, No.2 (2016)
  • U.S. Investment into Canada: Recent Developments – Tax Executive, Inc., November 2014.
  • Update on Surplus Stripping and PUC Stripping Following the Copthorne Decision, 64th Canadian Tax Foundation Tax Conference, 25-27 November 2012.
  • Break-fee Receipts: Expanding the Concept of Income, Corporate Finance, Vol.  XVIII, No.1 (2012).
  • Budget Proposal Regarding Specified Leasing Property Rules, Corporate Finance, Vol. XVI, No. 3 (2012).
  • Thin Capitalization – Where Are We Now?, Corporate Finance, Vol. XV, No. 4 (2009).
  • Leveraged Buy-Outs And Private Equity: Selected Issues inDebt Financing Acquisition, 59th Canadian Tax Foundation Tax Conference, 25-27 November, 2007 (presentation).
  • The Fifth Protocol to the Canada-U.S. Income Tax Convention, Corporate Finance, Vol. XIV, No. 3 (2007).