LAWYER PROFILE
Mark A Gelowitz

Mark A Gelowitz

Canada 2026

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Ranked in 1 practice area

About

Provided by Osler, Hoskin & Harcourt LLP

Practice Areas

Mark is a key contact for the firm’s Corporate and Securities Disputes Group. Mark has a business-focused civil and securities litigation, appellate and international commercial arbitration practice.

His practice covers a wide variety of issues in corporate and commercial law including mergers and acquisitions litigation, director and officer liability, corporate governance, shareholder disputes, oppression, privacy, libel and slander, real estate lease disputes, mining litigation and class actions.

Mark has appeared before the Supreme Court of Canada, the Ontario, Alberta, British Columbia and Yukon Courts of Appeal, the superior trial courts of numerous provinces and the Ontario and British Columbia Securities Commissions. Mark’s international commercial arbitration and investor-state arbitration experience includes major arbitration hearings conducted in London, Rome, Geneva, Tokyo, Warsaw and The Hague.

Mark completed two appellate judicial clerkships, the first with the late Chief Justice E.D. Bayda of the Saskatchewan Court of Appeal in 1986 and the second with the late Justice John Sopinka of the Supreme Court of Canada in 1989. He completed the B.C.L. degree at Oxford University in 1989, between his clerking experiences. Mark has had many important legal publications including a leading Canadian legal text for the last quarter-century, co-authored with the late Justice Sopinka entitled Sopinka and Gelowitz on the Conduct of an Appeal, Fifth Edition (Lexis/Nexis 2022).

Career

Oxford University, B.C.L.

Queen’s University, LL.B.

University of Regina, B.A.

Bar Admission: Ontario, 1991 | Saskatchewan, 1987

Professional Memberships

Advocates' Society

Ontario Bar Association

Metropolitan Toronto Lawyers' Association

Chambers Review

Provided by Chambers

Chambers Canada Guide

Litigation: General Commercial - Ontario

Band 2
Band 2

Individual Editorial

Mark Gelowitz has experience handling a broad range of disputes, including those in the technology, insurance, real estate and PE sectors. Based in Osler, Hoskin & Harcourt's Toronto office, he is additionally instructed for his representation in class action proceedings.

Strengths

Provided by Chambers

  • He is very capable and client-focused.

    Litigation: General CommercialChambers Canada Guide

Ranked Individuals at Osler, Hoskin & Harcourt LLP (199)

Alberta

British Columbia

Nationwide - Canada

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