Overview

Michael Rosenberg is a litigation partner in our Toronto office and vice chair of the firm’s National Class Actions Group. He maintains a general litigation practice, with a particular focus on class actions, complex commercial disputes and constitutional law.
Michael has argued cases at all levels of court, including the Supreme Court of Canada. He was recognized as Litigator of the Year and leader of the Commercial Litigation Team of the Year at the 2026 Canadian Law Awards.  Prior to joining McCarthy Tétrault, Michael served as a Law Clerk to the Right Honourable Beverley McLachlin, Chief Justice of the Supreme Court of Canada.
In addition to his private practice, Michael is an adjunct professor at the University of Toronto’s Faculty of Law, where he teaches class actions. He is also a member of the planning committee for the Osgoode Class Actions Symposium, a national conference, and he served as a member of the Law Commission of Ontario's advisory committee on class action reform.
Michael was awarded the Harvey T. Strosberg Prize in Class Actions Law in recognition of his research and writing in this field, and his work has been cited by the Supreme Court of Canada. Most recently, Michael joined Justice Ward Branch of the Supreme Court of British Columbia as a co-author of the looseleaf Class Actions in Canada, a leading text. Michael also co-authored the teaching text Class Actions in Canada, which is used in law schools across the country. Michael has been recognized by the Canadian Legal Lexpert Directory as a Leading Lawyer in the area of class actions.
Michael led the McCarthy Tétrault team representing the Canadian Civil Liberties Association in its landmark challenge to the constitutionality of prolonged solitary confinement in Canadian prisons. In 2017 this challenge struck down the legislation that authorizes the use of solitary confinement, and in 2019 the Court of Appeal for Ontario held that prolonged solitary confinement amounts to cruel and unusual treatment. Parliament responded with a major overhaul of federal correctional legislation.
Michael also led constitutional challenges to remedy the poor state of water infrastructure in First Nations across the country. In 2021, these class proceedings resulted in one of the largest settlements in Canadian history, valued at more than $8 billion. This ground-breaking agreement provides compensation to hundreds of First Nations and their members, together with commitments to build the water infrastructure that their communities require. The Federal Court and the Manitoba Court of Queen’s Bench noted counsel’s “expertise and focus” and heralded the settlement as a “hopeful turning point” and “a step down the long trail towards healing the relationship between Canada and First Nations”.
Michael led the successful defence of Pretium Resources Inc. and its chairman in the first secondary market securities class action in Canada to be dismissed on its merits.  Most recently, he prosecuted the largest legal fee assessment in Canadian history on behalf of Atikameksheng Anishnawbek and Garden River First Nation, which resulted in the return of more than $500 million.
Michael received his law degree with honours standing from the University of Toronto’s Faculty of Law. He holds a master’s degree in development studies from the University of Cambridge, awarded with distinction, and an undergraduate degree in social studies from Harvard University, where he graduated with high honours and was inducted into the Phi Beta Kappa honours society.
Litigator of the Year and leader of Commercial Litigation Team of the Year
Leading Lawyer: Class Actions; Litigation - Corporate Commercial; Litigation - Regulatory & Public Law
Arleen Goss Young Advocates’ Award for innovative and passionate advocacy, contribution to social justice, and commitment to the community.
Heather McArthur Memorial Young Lawyers' Award for exceptional contributions to legal education and the development of the law for the profession and the citizens of Ontario.
Speakers Dominique Amyot-Bilodeau, Kimberly J. Howard, Nicholas Hughes, H. Michael Rosenberg

Practice Areas

• Civil Litigation
• General Practice
• Information Technology Law

Bar Information

Called to the bar: 2010 (ON); 2010 (NY)