Gwyn Williams leads the firm’s product liability, mass torts, and consumer class actions litigation practice, drawing on nearly three decades of experience in a full range of courts.

Ms. Williams regularly defends clients in litigation related to: 

  • Consumer class actions
  • Consumer protection statues 
  • Mass and toxic torts 
  • Product liability claims
  • Personal injury / wrongful death claims
  • Complex commercial disputes

Her clients include manufacturers of retail products (including cigarettes), industrial products, and a wide range of pharmaceuticals and medical devices, as well as financial services companies.

She has handled complex, multi-defendant, and class action cases in nearly every combination of venues, including state and federal trial and appellate courts and administrative agencies across the United States and Canada.

Ms. Williams also regularly advises private equity firms and operating companies on diligence and liability risk assessment in the context of corporate transactions (including asbestos-related risk). She draws on her litigation experience across industries to counsel clients on product warnings, risk management, disclaimers of warranties, and indemnification strategies. 

Ms. Williams deftly helps clients navigate complex cases, often coordinating or collaborating with multi-defendant legal teams across jurisdictions. As clients pursue changing business objectives throughout the course of long-running litigation, Ms. Williams carefully calibrates litigation strategy and joint defense positions accordingly.

Leadership and Pro Bono

Ms. Williams serves on the global steering committee of Latham’s Women Enriching Business (WEB) initiative, and maintains an active pro bono practice, particularly focusing on juvenile justice and child welfare protection. Ms. Williams has been appointed as a Special Assistant Attorney General for the Commonwealth of Massachusetts and represents the Department of Children and Families in appeals before the Massachusetts Court of Appeals.

She frequently speaks at industry events and writes on issues relating to products liability and consumer class action defense, and issues relating to women in the legal profession. A Hotchkiss School alumna, she serves on the Board of Trustees and chairs the Board’s Development Committee.


Litigation Star
Benchmark Litigation 2023

Named to Lawdragon 500 2021-2022, an annual list of leading lawyers in America

Leading Lawyer – Product Liability Litigation: Defendants
The Best Lawyers in America 2020

Leading Lawyer – Product Liability, Mass Tort and Class Action: Defense category for Consumer Products and Toxic Tort
The Legal 500 US 2014-2022

Women Worth Watching
Profile in Diversity Journal 2017

Ms. Williams’ experience includes representing:

Retail and Consumer Products

  • Philip Morris International and Philip Morris USA in tobacco litigation defense, including: 
    • Class actions under consumer protection statutes seeking damages for alleged marketing misrepresentations (US and Canada)
    • Consumer class actions for personal injury, seeking damages (Canada) and/or medical monitoring (US)
    • Personal injury and/or wrongful death claims by individual smokers (US)
    • Aggregated smoking and health claims brought by union health funds (US)
  • Philip Morris International, Philip Morris USA, Altria Group, and Rothmans, Benson & Hedges in healthcare cost recoupment cases brought by each of the ten provincial governments in Canada, seeking C$100s of billions in smoking and health-related damages
  • Colgate-Palmolive and its subsidiary, Tom’s of Maine, in two separate class actions in federal district courts, the District of Massachusetts and the Central District of California, regarding Tom’s of Maine’s “natural” claims for its toothpastes and deodorants
  • Lands’ End in its defense against a consolidated class action, filed in federal court in Wisconsin, brought on behalf of Delta employees alleging uniforms made by Lands’ End caused personal injury and property damage
  • Juul Labs in connection with the development of the company’s new Code of Conduct and Global Compliance Policies

 Pharmaceuticals and Life Sciences 

  • Endo International in opioid cost recovery litigation, including:
  • MDL in Ohio federal district court with plaintiffs alleging deceptive marketing and oversupply of opioids leading to current crisis of opioid addiction and resulting costs to municipalities
  • 14 Massachusetts state court cases as lead counsel, coordinated for pre-trial purposes before the Superior Court’s Business Litigation Session, including cases by Massachusetts’ two largest cities as bellwether cases seeking damages for myriad costs associated with opioid addiction
  • Teva Pharmaceuticals as trial and coordinating counsel in significant product liability and consumer class action litigation involving the drug propofol*
  • A major pharmacy chain as national mass tort counsel (including in federal multidistrict litigation and multiple state courts), defending the issue of pharmacy liability for allegedly defective drugs such as “fen-phen,” OxyContin, and hormone replacement therapy*

Complex Commercial Litigation

  • One of the largest airline companies in the world in multiple class action lawsuits regarding baggage fees 
  • Caesars Entertainment and its subsidiaries in connection with COVID-19 related matters, including developing company protocols and communications for Caesars’ reopening after closing in March 2020 due to COVID-19
  • A multinational chemical company in a series of regulatory and litigation matters concerning the company’s alleged connection to certain per- and polyfluoroalkyl substances (PFAS, or so-called “forever chemicals”); matters include:
    • A nationwide class action filed in federal district court in Ohio seeking creation of a “science panel” and medical monitoring relief for virtually all US residents
    • MDL ongoing in the District of South Carolina regarding aqueous film-forming foams and PFAS-related claims
    • A suit filed by the State of Michigan to recoup damages for all harm allegedly caused by PFAS to the State’s natural resources
  • A major nuclear power producer in defense of citizen suits, rule-making challenges, and administrative law proceedings, including arguing appeals to the highest courts of Massachusetts and Vermont*

*Matters handled prior to joining Latham  

Bar Qualification

  • Massachusetts


  • JD, Boston University School of Law, 1993
    magna cum laude
  • AB, Princeton University, 1988