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Sonia  Bjorkquist

Sonia Bjorkquist

Partner, Litigation

Co-Chair: Class Actions

Key Contact: International Commercial Arbitration and ADR

Key Contact: Product Liability

Key Contact: Food Products

Contact Information

tel: 416.862.5876



Bar Admission

Ontario, 1997

  • Queen’s University, LL.B.
  • University of Waterloo, B.A. (Hons.)

Sonia has extensive experience defending companies in class actions and commercial arbitration, including advising clients on strategies for managing risks and cross-border issues in multi-jurisdictional cases. She defends complex product liability claims involving pharmaceuticals and medical devices, manufactured products, and food and beverages. She litigates business-critical issues related to commercial agreements, directors' duties and shareholder remedies. Sonia Co-Chairs  Osler’s Class Actions Specialty Group.

Sonia is ranked among Canada’s top litigators in Chambers Global (Dispute Resolution), Lexpert (Class Actions, International Commercial Arbitration, and Corporate-Commercial Litigation), Best Lawyers (Product Liability) and Benchmark. She is named as a leader in class actions in the Lexpert Guide to the Leading US/Canada Cross-Border Litigation Lawyers in Canada. She is rated AV Preeminent in Martindale Hubbell’s Peer Review Ratings. She is an elected member of the Federation of Defense and Corporate Counsel (FDCC) and a member of the Executive Committee of the Board of Directors of the Advocates’ Society. Sonia is a frequent speaker and author on class action and commercial arbitration issues.

Prior to joining Osler as a lawyer, Sonia clerked for the Court of Appeal for Ontario.

  • Benchmark Litigation Canada 2015: Arbitration; Class Actions (Future Star)
  • Martindale-Hubbell Peer Review Ratings: AV Preeminent (since 2013)
  • Chambers Global: The World’s Leading Business Lawyers 2015: Dispute Resolution – Ontario (since 2013)
  • The Canadian Legal Lexpert Directory: Leading Practitioner Consistently Recommended for Class Actions; Repeatedly Recommended for International Commercial Arbitration and for Litigation – Corporate Commercial
  • The Lexpert Guide to the Leading US/Canada Cross-Border Litigation Lawyers in Canada: Class Actions (since 2013)
  • The Best Lawyers in Canada: Product Liability Law (since 2013)

  • Walking the Tightrope: How to Manage Risk Today to Prevent Tomorrow's Class Action , Toronto

    October 1, 2015

  • Osler Pro Bono Community Law, international human rights matters and Canadian civil liberties matter

  • The Advocates’ Society, Executive Committee, Board of Directors
  • Federation of Defense and Corporate Counsel (FDCC), Elected Member
  • Defence Research Institute (DRI) Member
  • Toronto Commercial Arbitration Society (TCAS), Member, Past Member of Executive Committee
  • Young Canadian Arbitration Practitioners (YCAP), Advisory Board, Past Member of Board of Directors and Past Vice-President
  • ADR Institute of Canada, Past Member of Board of Directors
  • Canadian Bar Association (Ontario) Member
  • American Bar Association Member, Litigation Section
  • International Bar Association Member
  • Toronto Lawyers Association Member

  • A leading multinational pharmaceutical company in class actions and individual actions in several jurisdictions defending allegations of failure to warn
  • A leading medical device company in class actions and individual actions in several jurisdictions defending product liability claims
  • A leading manufacturer of automotive parts in a long private arbitration involving a long-term supply agreement
  • A leading environmental technology company in respect of the design and engineering of waste treatment equipment
  • A refinery in a long Ontario trial defending claims of alleged environmental contamination.
  • A multinational dairy company in litigation with an ingredient a supplier following a national Class I recall
  • The Receivers of Stanford International Bank in proceedings regarding the forfeiture of funds related to an international fraud and ponzi scheme
  • A major chartered bank in defending allegations of negligence and misrepresentation in individual and proposed class proceedings in three jurisdictions
  • The directors and officers of a bankrupt company in a New Brunswick class action involving allegations of breach of fiduciary duty in respect of the administration of company pension plans
  • A manufacturer of power transmission and distribution equipment in a long New Brunswick trial involving complex claims of breach of contract, negligence and failure to warn, including successfully defending an appeal taken to the Court of Appeal
  • A technology company in a long Ontario trial involving claims by a former senior executive for lost stock options
  • A leading financial processing services company in defence of claims by a former chief executive officer
  • A private investment company in a long Ontario trial arising from a breached share purchase transaction, as well as successfully defending appeals taken to the Ontario Court of Appeal and Supreme Court of Canada
  • Public and private sector organizations as respondents and affected third parties in access to information matters, investigations and hearings

  • The Oppression Remedy, Canada Law Book, loose leaf -- updated annually since 2004 (co-authored with D. Morritt and A. Coleman)
  • Getting to the Merits: Developments in Class Action Procedure in Common Law Canada, 2014, Colloque National sur les Recours Collectifs, Barreau du Québec, March 2015 (co-authored)
  • Drafting Dispute Resolution Clauses (co-authored), June, 2015
  • Arbitration Advocacy, Advocates’ Society, November 28, 2014 (co-chair)
  • Is Canada ripe for a food label fight? The Lawyers Weekly, November 26, 2014 (co-authored)
  • Taking Stock of Product Liability Food Claims in Canada, Law360, August 7, 2014 (co-authored)
  • Class actions for exaggerated health claims on the rise: report, by David Dias, Legal Feeds (Blog of Canadian Lawyer and Law Time), August 7, 2014
  • Just Enough:  Practical Boundaries of Certification, Colloque National sur les Recours Collectifs, Barreau du Québec, March 2014 (co-authored)
  • Class Action Waivers Different From Arbitration Agreements? Osler Canadian Class Action Defence Blog, November 22, 2013 (co-authored)
  • Interviewed in The Law Times, “Are Class Actions Going to Trial More Often?” by Julius Melnitzer, September 2, 2013
  • The Class of 2012: Where Are We Now?, Colloque National sur les Recours Collectifs, Barreau du Québec, March, 2013 (co-authored)
  • Class Actions in Canada 2012, Osler, Hoskin & Harcourt LLP, January 30, 2013 (co-authored)
  • Multi-Jurisdictional Classes: Does Van Breda Change Anything?, OBA Class Acts, Vol. 3, No. 1, December 2012 (co-authored with M. Paterson)
  • Litigating a Cross-Border Class Action in Canada, ALM Cross-Border Litigation Forum, New York, September 12, 2012
  • The New Emergency Arbitration Rules of the ICC, CBA National Section on International Law Newsletter, April 2012 (co-authored with E. Morgan)
  • Ethical Challenges in Arbitration Advocacy, Advocates’ Society Arbitration Advocacy, March 27, 2012 (Speaker)
  • Multi-jurisdictional Class Actions: Will the New CBA and ABA Protocols Solve all our Problems? Développements Récents en Recours Collectifs, Barreau du Québec, Vol. 345, March 2012 (co-authored with M. Eizenga and M. Paterson) (Speaker)
  • The Class Action Landscape for 2012: What In-House Counsel Needs to Know, Osler, Hoskin & Harcourt LLP, January 25, 2012 (Speaker)