Corporate and Securities Litigation

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Osler’s litigators have extensive experience representing public and private clients of all sizes in corporate governance, mergers and acquisitions and securities matters before the courts and provincial securities commissions.

We have been at the forefront of the development of legal principles governing a number of critical aspects of modern corporate law. As a result, we are intimately familiar with the potential risks involved in pursuing a course of action and can advise on the best approach to dealing with a litigious matter.

We work closely with our colleagues in related groups to provide comprehensive representation of our clients in Canada and cross-border. Our lawyers have advised and represented clients in corporate governance and securities litigation matters related to:

  • Corporate finance proceedings commenced under a variety of business statutes including the federal and provincial Business Corporations Acts and the provincial Securities Acts;
  • Securities class actions based on alleged misrepresentations contained in prospectuses, financial statements and other public disclosure documents;
  • Directors’ duties in hostile and friendly take-over bids;
  • Defending corporations in U.S.-style "strike" suits;
  • Directors’ personal liability for conduct undertaken on behalf of the corporation;
  • Shareholders’ rights;
  • Oppression remedy;
  • Dissent remedy and appraisal;
  • Derivative actions by shareholders;
  • Disputes in mergers and acquisitions;
  • "Poison pill" disputes.


Allan Coleman

Partner, Litigation


Mark A. Gelowitz

Partner, Litigation


Tristram Mallett

Partner, Litigation


Lawrence E. Ritchie

Partner, Litigation


Teresa Tomchak

Partner, Litigation


  • Mind Medicine

    Mind Medicine in its successful proxy contest against FCM MM Holdings, LLC

  • Nasdaq

    Nasdaq in its acquisition of Metrio

  • BP p.l.c.

    BP p.l.c. in Kaynes v BP

  • BP

    BP p.l.c. in a securities class action arising from the 2010 Deepwater Horizon explosion

  • GuestLogix Inc.

    GuestLogix Inc. in proposed securities class action alleging misrepresentations contained in company’s public disclosures relating to certain credit facilities

  • Find More

  • Chambers Canada: Canada’s Leading Lawyers for Business: Recognized in Litigation: Securities (Ontario) (Band 1)
  • The Canadian Legal Lexpert Directory: Recognized in Litigation – Securities (Toronto, Ontario)
  • Benchmark Litigation Canada Awards: Securities, Firm of the Year, Shortlisted (2019)