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Mark Tonkovich

Mark Tonkovich
Mark Tonkovich Partner | Toronto
Select Experience
  • Frontline or behind-the-scenes representation on a large number and variety of complex tax audits, including in the context of reviews by the Canada Revenue Agency’s (CRA) Aggressive Tax Planning Division, pertaining to issues such as transfer pricing, the foreign affiliate regime, entitlement to benefits under Canada's tax treaties, the reporting of offshore assets/investments, employee/independent contractor classification, and the scientific research and experimental development (SR&ED) program

  • Administrative appeals relating to matters as diverse as foreign accrual property income, non-resident withholding tax, payments in respect of intellectual property, the thin capitalization rules, errors in the presentation of financial information, income vs. capital characterization issues, federal sales tax and the financial service exemption, provincial sales tax on insurance products, and the scope and validity of provincial income tax assessments

  • Trial-level tax disputes involving the general anti-avoidance rule (GAAR), the taxation of foreign affiliates, transfer pricing adjustments, foreign entity characterization, the SR&ED program, and the tax consequences of employee/shareholder fraud

  • Appellate-level cases concerning the GAAR, business vs. property income issues, employer-provided taxable benefits, and the implementation of the provincial reassessment waiver regime

  • Applications for judicial review concerning failures by the CRA to issue timely assessments of federal income tax, compelling the refund of erroneously-remitted Part XIII withholding tax, disputing the validity of CRA audit requirements, challenging the CRA's refusal to provide relief from double taxation under the Canada-US Tax Treaty, and navigating the intersection of employment insurance and bankruptcy law

  • Counsel in the first CRA private inquiry (under s. 231.4 of the Income Tax Act) to be held in the past two decades

  • Appellate-level judicial intervention on behalf of the Canadian Bar Association concerning fundamental precepts of solicitor-client privilege and tax law advice

  • Provincial rectification proceedings to correct substantial transactional errors in a cross-border hybrid refinancing plan

  • Submissions to the CRA's Transfer Pricing Review Committee overcoming the proposed application of transfer pricing penalties

  • Voluntary disclosure submissions concerning a complex web of cross-border transactions involving dozens of legal entities, offshore asset reporting issues, and substantial errors under various provincial sales tax regimes

  • Post-transaction opinions on specific tax risks, focusing on the viability of client tax positions and the proactive management of litigation risks and other sensitive matters

Awards & Recognition

Mark is recognized as a leading tax lawyer in the following publications:

  • The Legal 500 Canada 2020 (Tax)

  • World Tax/International Tax Review’s Tax Controversy Leaders 2020 – Highly Regarded

  • Chambers Canada: Canada’s Leading Lawyers for Business 2020 (Tax Litigation)

  • The Best Lawyers in Canada 2020 (Tax Law)

  • World Tax/International Tax Review’s Tax Controversy Leaders 2019 – Highly Regarded

  • The Best Lawyers in Canada 2019 (Tax Law)

  • International Tax Review's Tax Controversy Leaders Canada 2018

  • International Tax Review's Tax Controversy Leaders Canada 2017

Professional Activities

Mark is a frequently published author. He has written or co-written dozens of articles on Canadian tax matters, including in the peer-reviewed Canadian Tax Journal and the National Journal of Constitutional Law, as well as in several trade publications. He also sits on the editorial board of Tax Litigation, a Federated Press journal.

Mark is a member of the Tax Court Bench and Bar Committee, a board member of the Toronto Centre CRA & Tax Professionals Group, and a past chair of the Ontario Bar Association’s Taxation Law Section. He is also a member of the Canadian Tax Foundation, The Advocates' Society, the Canadian Bar Association, the Canadian Petroleum Tax Society, the International Fiscal Association, the Halton County Law Association, and the Ukrainian Canadian Bar Association.

Mark regularly speaks at events for tax professionals and has appeared as an invited witness before the House of Commons Standing Committee on Finance.

Mark has also provided many hundreds of hours of pro bono public-interest representation to select organizations and low-income individuals. He is a founding board member and serves as secretary of the non-profit Making the Shift Inc., a youth homelessness social innovation lab that has been granted $17.9 million in funding from the Canadian government to address and prevent youth homelessness. Mark also volunteers as a judge for a variety of moot court competitions (including the Bowman National Tax Moot, the Canadian rounds of the Jessup International Moot, and the OBA/OJEN High School Mock Trial Competition).

  • Co-author: Striking a Balance: Exploring Legitimate Expectation and the Fisc's Administrative Positions in Canada, the UK, and the US
    Tax Litigation, Vol. 22, Issue 2, p. 2, Federated Press, 2019.
  • Co-author: Future Law and Alternative Facts in the GAAR Analysis
    Tax Litigation, Vol. 21, Issue 1, p. 6, Federated Press, 2018.
  • Co-author: After IGGillis Holdings: Protecting privilege when giving common legal advice
    CBA National, March 26, 2018.
Professional Appearances
  • Chair: Part I: Information Demands on Audit and at Discovery and Part II: Accessing Government Information on Audit and at Discovery
    71st Annual Tax Conference, Canadian Tax Foundation, December 2019.
  • Panellist: Privilege and confidentiality - an update
    The New Era of Taxation, International Bar Association, November 2019.
  • Co-presenter: CRA Audit Updates / Best Practices Seminar
    Ontario Tax Conference, Canadian Tax Foundation, October 2019.
  • Co-presenter: Transfer Pricing – Law and Practice
    International Fiscal Association YIN Seminar, IFA Canada, March 2019.
  • Co-presenter: Current Cases Seminar
    Ontario Tax Conference, Canadian Tax Foundation, October 2018.
  • Mentor: Speed Mentoring – Practical Advice on Succeeding as a Young Tax Lawyer
    Taxation Law Section Seminar, Ontario Bar Association, October 2018.
  • Panellist: Best Practices to Deal with Canadian Tax Authorities and Audits
    Canadian Tax Workshop for US Companies, Council on State Taxation, September 2017.
  • Panellist: Need to File an Appeal – Procedures to Object and Appeal Canadian/Provincial Tax Assessments and Customs/Duties (Including Input GST)
    Canadian Tax Workshop for US Companies, Council on State Taxation, September 2017.
  • Chair: Year-End Address
    Taxation Law Section Year-End Seminar, Ontario Bar Association, June 2017.
Media Activities
  • Quoted: AI in Tax Law
    Interviewed by Jean Cumming, Lexpert/ROB Special Edition on Leading Litigation Lawyers, November 29, 2019.
  • Quoted: Federal Court of Appeal gives guidance to CPP filing obligations of retired business partners
    Interviewed by Terry Davidson, The Lawyer’s Daily, June 18, 2018.
  • Quoted: Federal Court of Appeal clarifies reach of solicitor-client privilege
    Interviewed by Amanda Jerome, The Lawyer's Daily, March 14, 2018.
  • Quoted: The CBA’s intervention on common interest privilege
    Interviewed by Yves Faguy, CBA National Magazine, October 5, 2017.
Admitted to the Ontario Bar – 2009
LL.M. (Tax), Osgoode Hall Law School – 2014
LL.B. (Distinction; Lord Beaverbrook Scholar), University of New Brunswick – 2008
B.A., University of Guelph – 2005
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