Thomas Yoo is a litigator and Chair of the firm's national Products Liability Life Sciences Practice Group. He is recognized as one of the “Top 100 Lawyers” in the State of California by the Daily Journal. With a practice focused on product liability matters, consumer class actions, and commercial disputes, Thomas has served as national, regional and trial counsel and in other strategic roles on behalf of leading companies in numerous industries, including life sciences, manufacturing, food products, financial services, real estate, and private investment ventures. Thomas has been involved in some of the highest profile mass tort litigations in the country, including being selected by the courts for defense leadership appointments in federal multidistrict litigations (MDL) and statewide coordinated proceedings such as Vioxx, NuvaRing, and Zantac.

Thomas’s representations include the defense of clients in litigations involving pharmaceutical, medical device, food, consumer, and industrial products, including In re Zantac Litigation (MDL 2924, Southern District of Florida and 11th Circuit Court of Appeals), In re Baby Food Litigation, (MDL 3101, Northern District of California), and In re Port Catheter Litigation (MDL 3125, Southern District of California), purported class actions involving benzoyl peroxide and potassium chloride drug products and listeria-related recalls of food products, and high exposure cases involving catastrophic injuries, fires, and explosions.  He has successfully defended cases in courts across the country, including in California, Alabama, Colorado, Hawaii, Illinois, Indiana, Kentucky, Louisiana, Maryland, Massachusetts, Michigan, Nevada, New Jersey, New York, New Mexico, North Carolina, Ohio, Pennsylvania, South Carolina, Texas, Utah, Washington, and West Virginia.    

In Legal 500 USA's annual national rankings of top law firms, Thomas is described as "an excellent strategist." He is also recognized by Chambers, in Product Liability & Mass Torts, USA - Nationwide, with clients stating: “Thomas is an excellent litigator,” “very knowledgeable in this field,” and "very level-headed, smart and strategic." "He's quick in court, insightful and has good instincts." "Thomas is a very good communicator" and "Thomas has one of the sharpest minds I have worked with." He is recognized by Who's Who Legal in Life Sciences and Product Liability Defense: Global Leader, and has also been quoted on legal issues in numerous media outlets, including CNN, CNBC, Reuters, Fox News and The Los Angeles Times.

Thomas handles a wide range of complex cases, negotiations and exposures, from prescription pharmaceuticals and medical devices to environmental toxic exposure matters, from mass torts involving thousands of cases to individual contract actions. He has in-depth experience in cross-border business disputes, federal multidistrict litigation (MDL) and statewide coordinations, class action defense, cases alleging violation of various state consumer protection statutes such as California's Consumer Legal Remedies Act (CLRA) and Section 17200/17500, and high-profile matters garnering national media attention.

Thomas defends his clients with a comprehensive understanding of the scientific issues implicated in the litigation. Thomas has worked with leading scientists and medical doctors and has handled the cross-examination and Daubert challenges of experts in a variety of fields, including cardiology, neurology, oncology, epidemiology, gynecology, pulmonology, immunology, interventional radiology, pharmacology, toxicology, hematology, infectious disease, metallurgy, mechanical engineering, electrical engineering, biomaterials science, food safety, microbiology, vascular biology, rheumatology, and pharmacokinetics.