Blake, Cassels & Graydon LLP

Litigation ＆ Dispute Resolution; Tax

Mark Tonkovich’s practice focuses exclusively on resolving Canadian tax disputes. He represents many of Canada’s and the world’s largest and most sophisticated businesses in tax-related civil litigation, administrative appeals, audit defence, and in proactively managing tax dispute risks. Mark has successfully acted for taxpayers at all levels of court, with the Federal Court of Appeal describing his work as "exemplary" in a 2013 judicial review application. He draws on Blakes' top-tier national tax practice to develop and execute comprehensive and practical strategies for resolving tax disputes as efficiently and favourably as possible, both within and beyond the courtroom.

Mark frequently writes and presents on tax issues for leading professional and industry organizations. He is a member of the editorial board of the journal Tax Litigation, and he previously chaired each of the Tax Court Bench and Bar Committee and the Ontario Bar Association’s Taxation Law Section. He has written dozens of articles on Canadian tax matters, including in the peer-reviewed Canadian Tax Journal and the National Journal of Constitutional Law. Earlier in his career, Mark served as an appellate judicial clerk and as a tax litigator with the Department of Justice. He is recognized in every major Canadian tax/tax litigation lawyer ranking.