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David Ziegler Toronto Lawyer

David A. Ziegler

Partner Fasken
Recent high-profile cases have highlighted the seriousness with which the courts view the misuse of confidential corporate information by competitors.
Jurisdiction Ontario, 2015 | New York, 2011
Language(s) English
Office(s) Toronto
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Overview

David Ziegler’s robust civil litigation and arbitration practice encompasses business-critical commercial and financial disputes, class actions, product liability matters, construction matters (including adjudications), and disputes requiring international arbitration. His vast experience acting for both Canada- and US-based companies is sought after for domestic and cross-border disputes, spanning a broad range of industries including mining, rail, professional services, insurance, banking and finance, accounting, manufacturing, and construction. He is also routinely trusted to advise clients on the enforcement and recognition of foreign judgments in Canada.

A dual-qualified lawyer in New York and Ontario, David leverages experience in securities litigation and general commercial disputes gained while practicing with a leading international law firm in New York, prior to joining Fasken.

Adept in managing large and complex e-Discovery projects, David also advises clients on best practices related to document preservation and collection, the preparation and circulation of litigation holds, and the use of modern data processing tools. He leads an initiative at Fasken to ensure that the Firm maintains and provides a state-of-the-art e-Discovery process for clients.

David maintains an active portfolio of pro bono engagements. He oversees several matters in connection with the TAS-PBO Consumer Protection Initiative – a partnership between The Advocates’ Society (TAS) and Pro Bono Ontario (PBO) – that assists low-income consumers facing the effects of predatory door-to-door sales. David has previously volunteered at the Toronto Small Claims Court in a Duty Counsel capacity, advocating for unrepresented litigants as part of PBO’s Duty Counsel Project.

Achievements

Experience

  • Cook companies resolve class action concerning inferior vena cava filter products, [Case - The Defendants, Cook (Canada) Inc., Cook Incorporated, and William Cook Europe APS (collectively, “Cook”)], Canadian medical device company resolves product liability class action lawsuit.
  • Golden Star Resources Ltd. closes US$470 million plan of arrangement with Chifeng Jilong Gold Mining Co., Ltd., Chijin International (Hong Kong) Limited and its assignee Kefei Investment (BVI) Limited, [Deal - Golden Star Resources Ltd.], Established gold mining company that owns and operates the Wassa underground mine in West Africa acquired by international gold mining company via plan of arrangement.
  • French defendants achieve permanent stay of Ontario lawsuit following jurisdictional challenge, [Case - Two French Residents], Foreign defendants succeed on jurisdictional arguments.
  • Guyana Goldfields Inc. defends proposed securities class action for alleged misrepresentations about business and operations, [Case - Guyana Goldfields Inc.], A Canadian company with gold mine ownership in Guyana defends proposed securities class action.
  • Sleep Number Corporation v. Maher Sign Products Inc. 2020 ONCA 95, [Case - Sleep Number Corporation], Successfully represented Sleep Number Corporation in obtaining a favourable Ontario court of appeal decision regarding the enforcement of a U.S. judgment.
  • Windsor-Detroit Bridge Authority achieves financial close Gordie Howe International Bridge Project, [Deal - Windsor-Detroit Bridge Authority], On September 28, 2018, Windsor-Detroit Bridge Authority, a Crown corporation of the Government of Canada, reached financial close with Bridging North America General Partnership (a partnership indirectly held by ACS Infrastructure Canada Inc., Fluor Canada Ltd. and Aecon Concessions, a division o...
  • Confidential client in ICC arbitration valued at C$220 million, [Case - Confidential Client], Represented the Claimant in two related ICC arbitrations seated in Toronto with $220 million in claims related to the termination of an EPCM contract for a mine in Central America.
  • Canadian National Railway Company v. Canadian Pacific Railway Company, 2015 ONSC 6843, [Case - 0930032 B.C. Ltd.], Read the decision: Canadian National Railway Company v. Canadian Pacific Railway Company, 2015 ONSC 6843
  • Catucci v. Valeant Pharmaceuticals International, Inc. et al., [Case - PricewaterhouseCoopers LLP]

Career & Education

Education

  • JD Fordham Law School
  • BA Wesleyan University

Community involvement

  • Pro Bono Law Ontario Duty Counsel Project

Memberships & Affiliations

  • Member, Law Society of Upper Canada
  • Member, Canadian Bar Association
  • Member, Advocates’ Society
  • Member, Young Canadian Arbitration Practitioners
  • Member, New York State Bar Association
  • Member, International Arbitration brainstorming group, Sedona Conference Working Group 6
  • Member, Canada Advisory Board, International Institute for Conflict Prevention & Resolution
  • Member, International Institute for Conflict Prevention & Resolution Task Force on Remote Video Arbitration Proceedings

Knowledge

  • Good Faith, Contractual Discretion, and Tariffs: What In-House and Corporate Counsel Need to Know, 5/22/2025
  • The Benefits of Choosing a Canadian Jurisdiction for Choice of Law and Jurisdiction in Contracts, 3/13/2025
  • Important Legal Considerations for the Impact of Tariffs on Cross-Border Contracts, 2/3/2025
  • Can I Be Compelled to Give Evidence in a US Lawsuit? A Recent Case on Letters Rogatory..., 8/30/2023
  • Ontario Court of Appeal Reaffirms Narrow Power to Set Aside Arbitration Award for Lack of Jurisdiction, 11/21/2022
  • Supreme Court of Canada Expands Duty of Honest Performance, 1/21/2021
  • Where to Sue - A Primer on Enforcement of Foreign Judgments in Canada, 5/7/2020

Events

News

Publications

  • Québec Superior Court annuls arbitral award due to fictitious authorities "hallucinated" by AI, 5/7/2026
  • Ontario Superior Court enforces CIETAC award rejecting incapacity and public policy defences as collateral attack, 4/20/2026
  • Ontario Superior Court Grants Anti-Suit Injunction Restraining Hong Kong Arbitration in Binance Class Action, 12/16/2025
  • Tariffs, good faith and contractual discretion: Top tips for in-house, corporate counsel, 6/9/2025
  • Ontario Superior Court Bound to Recognize ICSID Award, 5/28/2025
  • Ontario Court of Appeal sets aside award based on reasonable apprehension of bias, 2/14/2025
  • Enforcing ICSID Convention Arbitration Awards in Canada: Overview, 2/4/2025
  • Ontario Court of Appeal Overturns Finding of Reasonable Apprehension of Arbitrator Bias, 12/9/2024
  • Ontario Court of Appeal Affirms Lower Court’s Decision to Set Aside Arbitration Agreement in Consumer Contract in Class Action, 11/21/2024
  • Applications: Letters Rogatory (ON), 10/4/2024

Speaking Engagements

  • Priority PD: Mitigation Strategies for Commercial Contracts and Cross-Border Business, 3/26/2025
  • Managing Extraordinary Risk: The Case for Conflict Prevention, 9/21/2021
  • Misuse of Corporate Confidential Information, 11/18/2016