John Carlo Mastrangelo

T 416 956 0101 F 416 598 3730
John Carlo is a methodical litigator who enjoys tackling complex legal problems. He delivers solutions that are innovative, analytical and results driven.

John Carlo carries a broad litigation practice with particular interests in corporate-commercial litigation and regulatory/public law. He has played pivotal roles in numerous significant litigation matters including a precedent-setting CRTC appeal, a First Nations historic Treaty claim and the largest contested merger in Canadian history.

He has also served as counsel to clients across multiple industries including telecommunications, energy and real estate. John Carlo has appeared at all levels of court in Ontario, before the national Competition Tribunal and the Supreme Court of Canada.

John Carlo received his J.D. from Osgoode Hall Law School, where he graduated as the gold medallist, and won a range of subject-matter prizes. Before joining the firm, John Carlo served as a law clerk to the Honourable Suzanne Côté at the Supreme Court of Canada.




  • Called to the Ontario Bar, 2018
  • Clerkship: Justice Suzanne Côté, Supreme Court of Canada
  • J.D., Osgoode Hall Law School, 2017
  • Undergraduate studies at Glendon College, York University
  • The Best Lawyers™ in Canada: Ones to Watch, 2024: Administrative and Public Law