Toronto-based litigation boutique Paliare Roland Rosenberg Rothstein LLP is a significant player in the Ontario market, known for its expertise in corporate commercial litigation, class actions, insolvency litigation, securities litigation and product liability matters, among others. At the helm of the practice, Emily Lawrence has substantial expertise in professional regulation, pension litigation, constitutional litigation, civil disputes and privacy matters. Ken Rosenberg has notable experience in mediation and arbitration, as well as commercial litigation, class action and administrative disputes. Additional key contacts include Odette Soriano, who handles class action and defamation matters on both the plaintiff and defence sides; and Linda Rothstein, who specializes in professional regulation matters and internal partnership disputes. Jeffrey Larry brings expertise in securities and insolvency litigation.

Blake, Cassels & Graydon LLP‘s Ontario group is recognized for its expertise in commercial litigation, securities litigation, IP litigation, class action and product liability matters, as well as arbitration. The team is frequently retained by clients in the automotive, energy, transportation and aerospace segments. The group is co-led by Catherine Beagan Flood and Iris Fischer; Beagan Flood has focused her practice on commercial disputes, including appeals and class actions on privacy, antitrust, product liability, insurance and consumer protection issues. Fischer, for her part, has particular expertise in the media and defamation space. Additional key litigation-focused partners include Michael Barrack, Jeff Galway and Gordon McKee. Bradley Berg is another name to note.

Toronto-based boutique Lax O'Sullivan Lisus Gottlieb LLP is a leading player in the Ontario disputes space. The ‘outstanding team of lawyers’ is well-versed in representing both domestic and international clients in complex commercial mandates. Practice co-head Matthew Gottlieb specializes in corporate and commercial disputes, and insolvency, fraud and securities litigation. Leading alongside him, Jonathan Lisus has focused his practice on infrastructure and P3 disputes, product liability claims and securities litigation. Additional key litigators include Crawford Smith, Andrew Winton and Shaun Laubman. Nadia Campion handles shareholder oppression applications and estates matters and is lauded as ‘completely fearless’ and an ‘outstanding litigator’. Paul Fruitman is noted for his work on construction, employment health disputes, while Rahool Agarwal majors on proxy fights, director and officer liability, and complex fraud cases.

McCarthy Tétrault houses a strong Ontario disputes practice which counts class action, product liability, professional liability and securities litigation, as well as white-collar defence, arbitration and regulatory matters, among its specialties. The team is regularly engaged in disputes touching on mining, environmental, Aboriginal and energy matters. Arbitration, technology, professional negligence and contractual disputes specialist Thomas N.T. Sutton heads up the almost 140-strong group. Paul Steep majors on securities litigation and has experience appearing before all levels of Ontario courts, as well as the Supreme Court of Canada; Sarit Batner has particular experience in matters involving breach of contract, professional negligence and shareholder disputes. Junior Sirivar chairs the firm’s international arbitration group and is well-versed in mining, banking, healthcare and telecoms disputes. Other key names include Moya Graham, Christine Lonsdale and Adam Goldenberg. Eric Block left the firm in July 2023.

The Ontario team at Bennett Jones LLP is known for its handling of cross-border restructuring, fraud, class actions, insolvency, energy, mining, technology and M&A disputes. Practice head Richard Swan specializes in complex commercial litigation and arbitration matters and has experience representing clients before all levels of the Ontario and Federal Courts. Additional key department figures include Robert Staley, who handles commercial and securities litigation, securities regulation and class actions; and commercial litigation and class proceedings specialist Michael Eizenga, who takes care of product liability and class action matters. Other key names include Cheryl Woodin and Jeffrey Leon KC.

Torys‘ Toronto-based group routinely represents a range of domestic and international companies in shareholder litigation, breach of contract and corporate governance matters. The practice is co-led by Linda Plumpton, who is focused on competition litigation, securities litigation, class action defence, and corporate and commercial disputes. Alongside her, Gillian Dingle routinely supports leading capital market players in professional liability claims, securities class actions and regulatory investigations. Additional key figures include Sheila Block, who demonstrates expertise in IP, defamation and administrative law disputes, and Sarah Whitmore, who handles employment, media and public law disputes. Another key figure is seasoned litigator Andrew Bernstein.

The Ontario practice at Borden Ladner Gervais LLP services clients across a range of sectors, including financial services, mining, healthcare, retail and real estate. The group is noted for its participation in class action defence, investigations, commercial fraud and white-collar crime proceedings, in addition to financial institution, securities and banking-related matters. A trio of partners co-lead: David Di Paolo handles securities litigation, class actions and shareholder disputes; Nadia Effendi specializes in class actions as well as administrative and regulatory matters; Ottawa-based Kathleen McDormand completes the leadership team.

The Ontario group at Dentons offers clients support on commercial litigation, insurance litigation, shareholder dispute litigation, product liability litigation and class actions. Its varied client roster regularly features mayor players in the tech, retail, metallurgical, transportation, finance and insurance segments. Practice head Douglas Stewart majors on commercial and civil litigation with an emphasis on professional liability and insurance related matters. Key partner Matthew Fleming has forged a prominent reputation for class action, professional and product liability, regulatory and securities-related disputes. Other noted figures include experienced litigators Marina Sampson and Michael Schafler.

Fasken‘s Ontario group is regularly instructed by financial institutions and companies in the mining, health, energy, life sciences, construction, transportation and technology segments for its expertise in commercial dispute resolution. The team also demonstrates expertise in cybersecurity, securities, competition, insurance and employment class actions, as well as regulatory and civil securities issues. Practice head Sarah Armstrong leads from Toronto and supports clients on commercial dispute, professional liability and administrative law matters, both in court and in arbitration. Peter Pliszka has focused his practice on product liability, class action, commercial and insurance litigation matters, while Peter Mantas leads on litigation matters from the Ottawa office. Other key figures include vice chair Vera Toppings, who handles complex arbitrations and associate Pavel Sergeyev.

Gowling WLG‘s Ontario-based group is known for its activity in aviation, insolvency and restructuring, banking, procurement, white-collar crime and competition-related disputes. The firm boasts five Ontario bases, spanning Hamilton, Ottawa, Toronto and Kitchener. Key department figures include Scott Kugler, whose focus is on complex commercial disputes, including class actions and shareholder disputes; and Natalie Mullins, well-versed in civil litigation and environmental law – she focuses her practice on complex contaminated lands disputes. Other key figures include Sandra Barton, who brings extensive experience to contractual disputes, and Sahil Shoor, who specializes in matters related to construction and infrastructure.

Working from offices in Toronto and Ottawa, the Ontario group at Norton Rose Fulbright is well-versed in representing financial institutions, pharmaceutical, life science and insurance companies in litigation. The team’s M&A litigation capabilities are bolstered by close collaboration with the firm’s corporate, M&A and securities practice. Ottawa-based Tate McLeod brings expertise in advising clients in finance and in the transport sector. Orestes Pasparakis is noted for his knowledge on restructurings and proxy disputes; Jennifer Teskey chairs the national litigation department and has appeared before all levels of the Ontario courts. Associate Anisha Visvanatha specializes in competition and antitrust matters. Practice co-head Linda Fuerst departed in January 2024.

Cassels Brock & Blackwell LLP's Ontario group has a track record representing clients before all local Courts of Appeal, in addition to the Supreme Court of Canada. The team handles a range of disputes, from shareholder disputes, class action, M&A and tax-related litigation to defamation matters. National department head John Birch leads from Toronto and specializes in restructuring and insolvency proceedings.

The 15-strong Ontario team at DLA Piper (Canada) LLP is led by national group co-head David Foulds, who operates from Toronto. Foulds handles a variety of commercial disputes ranging from breach of contract cases to shareholder disputes and product recall cases. His team has additional expertise in commercial fraud matters, infrastructure projects and class action litigation.