- Bio
- Recognition
- Engagement
- Featured Work
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John's advocacy is tried and tested, having conducted dozens of lengthy and complex arbitrations, trials, and administrative hearings. John has a robust appellate practice, having appeared at the Court of Appeal for Ontario on over 40 appeals and before the Supreme Court of Canada on multiple occasions.
John does not shy from challenge. Some of John’s most notable cases are the product of his creative, boundary-testing approach, and passion for applying the law creatively to achieve sensible outcomes and promote access to justice:
- Successfully trying several oppression cases before the Ontario Superior Court's Commercial List;
- Successfully acting for appellants overturning trial decisions, including in one of the largest damages awards of its kind in Ontario history;
- A claim against the Republic of Iran that was the first claim against a foreign state under Canada’s Justice for Victims of Terrorism Act;
- Acting for members of the family of the late Honey Sherman in a claim against a trust set up by Canadian business icon Barry Sherman;
- Acting for the plaintiffs in a class action against Facebook (Meta) and Instagram for psychological harm done to users; and
- Acting in numerous family business and/or partnership disputes where there is more than $100 million in issue.
For his excellence in litigation, John is consistently recognized as a leading litigator by his peers and leading publications, including by Chambers, Lexpert, Benchmark, and Best Lawyers. He has been listed each year since 2022 as one of Canada' 500 leading lawyers. John also frequently acts on a pro bono basis in legally important cases, including disputes over the constitutionality of Ontario's school curriculum and regarding the liability arising from medical clinical trials.
John’s passion for advocacy extends beyond casework. John is regularly invited to speak at conferences and conduct advocacy demonstrations. He has authored numerous articles related to litigation issues, including evidence and expert witnesses, and received the David Stockwood Memorial Prize, awarded biannually by The Advocates’ Journal. John is a former co-chair of the Advocates’ Society Commercial Litigation Practice Group.
John is an engaged alumnus of the University of Toronto Faculty of Law, where he is invested in developing and supporting new lawyers. He has served as an instructor of Trial Advocacy, mentored students through the Alumni-Student Mentorship Program, and is presently an Adjunct Professor of Access to Justice and the Legal Process.
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Lexpert® Special Edition: Litigation
Recognized as one of Canada's Leading Litigation Lawyers
2016, 2018, 2022, 2023-2024 -
Toronto Post
Toronto's Best Lawyers, Appellate Law
2022-2024 -
Chambers & Partners
Litigation: General Commercial, Band 5
2017-2025 -
Benchmark Litigation
Litigation Star
2019-2024 -
Canadian Lexpert® Directory
"Most Frequently Recommended" for Litigation - Corporate Commercial
2014-2024 -
Canadian Lexpert® Directory
"Repeatedly Recommended" for Litigation - Directors' & Officers' Liability
2014-2024 -
Canadian Lexpert® Directory
"Consistently Recommended" for Litigation - Professional Liability
2014-2024 -
Canadian Lexpert® Directory
"Repeatedly Recommended" for Litigation - Regulatory & Public Law
2014-2024 -
Best Lawyers™
Recognized for Appellate Practice, Corporate & Commercial Litigation, and International Arbitration
2021-2025 -
Canadian Lexpert® Directory
"Repeatedly Recommended" for Litigation - Directors' & Officers' Liability
2024 -
Lexpert®/American Lawyer Magazine 500
"Most Frequently Recommended" for Corporate Commercial Litigation
2024 -
Canadian Lexpert® Directory
Recognized as one of Canada's leading cross-border litigation lawyers
2023 -
Chambers & Partners
"Up and Coming" Litigation Lawyer
2017 -
Lexpert®
Lexpert® Rising Star: Leading Lawyers Under 40
2014
Memberships + Legal Leadership
- Member, The Advocates' Society
- Former Co-Chair, Commercial Litigation Practice Group ,the Advocates’ Society
Teaching
- Adjunct Professor, University of Toronto, Access to Justice and the Legal Process
- Instructor, Trial Advocacy Program, University of Toronto
- Mentor, University of Toronto, Alumni-Student Mentorship Program
Community
- Volunteer coach, Holland Bloorview Kids Rehabilitation Hospital
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Marketology Media Inc. v. DGA North American Inc.
2024 ONCA 799
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Hasan v. Trillium Health Centre (Mississauga)
2024 ONCA 586
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Hemmings v. Peng
2024 ONCA 318
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1000425140 Ontario Inc. v. 1000176633 Ontario Inc.
2023 ONSC 6688
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Canada (Attorney General) v. Al Jabri
2023 FC 1338
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Sakab Saudi Holding Company v. Saad Khalid S Al Jabri
2021 ONSC 7681, 2023 ONSC 2488
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Sokoloff v. Chorney
2023 ONSC 362
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Farej v. Fellows
2022 ONCA 254
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Stirrett v. Cheema
2020 ONCA 288
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Tomec v. Economical Mutual Insurance Company
2019 ONCA 882
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ETFO et al v. Her Majesty the Queen
2019 ONSC 1308
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Mamado v. Frisdon
2018 ONCA 806
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Tracy v. Iran (Information and Security)
2017 ONCA 777
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Levine v. 1751060 Ontario Inc.
2016 ONSC 3961, 2016 ONSC 6418
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Longo v. McLaren Art Centre
2014 ONCA 526
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Bennett v. Islamic Republic of Iran
2013 ONCA 623
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Crinson v. City of Toronto
2010 ONCA 44
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Canadian Premier Life Insurance Co. v. Sears Canada Inc.
2010 ONSC 3834
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AGB successfully defends appeal despite insufficiency of reasons
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AGB continues to rise in Chambers Canada 2025
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12 AGB lawyers recognized by Best Lawyers
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AGB lawyers successful in medical negligence appeal
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AGB lawyers shine in the 2024 Benchmark Litigation Canada Guide
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AGB protects solicitor-client privilege amid allegations of civil fraud
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AGB lawyers identified as Leading Practitioners in the 2024 Canadian Legal Lexpert Directory
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John Adair named among Lexpert/ALM 500 leading lawyers in Canada
Bar Admissions
- Ontario, 2006
Clerkships
- Court of Appeal for Ontario
Education
- JD, University of Toronto, 2005
- BA (Honours), Queen’s University, 2001