Mark A Gelowitz is a senior litigation partner at Osler. He is the co-chair of the firm’s national corporate and securities litigation 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, oppression, mining litigation and class actions. He 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 completed two appellate judicial clerkships, the first with the late Chief Justice ED 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 BCL degree at Oxford University in 1989, between his clerking experiences. Mark has had a number of legal publications including a book co-authored with the late Justice Sopinka entitled The Conduct of an Appeal (third edition, LexisNexis, 2012). Mark maintains a blog on recent developments in Canadian appellate law and practice at