Jonathan Tam is a partner in the Litigation Department and member of the Mass Torts & Product Liability practice group. He represents major pharmaceutical companies, medical device companies and consumer electronic companies, and other innovative companies in their most complex and high-stakes product liability litigations, mass torts, class actions, and civil actions filed by state attorneys general.
Tam has significant experience litigating complex cases in federal and state courts nationwide, including at trial and on appeal, with a focus on high-stakes mass tort and product liability litigations. He has particular experience litigating the admissibility of expert testimony, winning key motions excluding plaintiffs’ experts’ causation testimony that led to summary judgment for Pfizer and Allergan in three major products liability litigations.
Lawdragon Honors
| Honor | Year | Practice |
|---|---|---|
| The 2026 Lawdragon 500 Leading Litigators in America | 2026 | Product Liability, Mass Tort Litigation |
Tam’s experience includes:
- Monsanto in a two-and-a-half month, consolidated trial where 15 plaintiffs alleged injuries from their exposure to PCBs at Sky Valley Education Center, securing complete defense verdicts as to 11 of the 15 plaintiffs.
- Johnson & Johnson as trial counsel in product liability litigation where the plaintiffs alleged that J&J’s talcum-based baby powder products contained asbestos that caused the plaintiffs to develop mesothelioma.
- 3M as trial counsel, notably securing multiple favorable trial verdicts, in a multibillion-dollar product liability litigation, recognized as the largest federal multidistrict litigation in history, involving allegations that a product sold to the military is related to hearing loss suffered by servicemen and women.
- Allergan in product liability cases involving novel claims that maternal use of an antidepressant during pregnancy causes autism in children, obtaining the exclusion of plaintiffs’ general causation experts and securing the affirmance of the decision in the U.S. Court of Appeals for the Second Circuit.
- Pfizer in several significant litigations, including in:
- a California Judicial Council Coordinated Proceeding involving thousands of cases alleging that Lipitor, a cholesterol-lowering medication, causes diabetes. Jonathan obtained the exclusion of plaintiffs’ general causation expert under Sargon Enterprises, Inc. v. University of Southern California, 55 Cal. 4th 747 (2012);
- an appeal to the U.S. Court of Appeals for the Fourth Circuit involving thousands of cases that alleged that Lipitor causes diabetes. Jonathan obtained affirmance of the exclusion of plaintiffs’ general causation experts and summary judgment for Pfizer in all cases
- GlaxoSmithKline in several litigations, including in:
- a federal multidistrict litigation and California Judicial Council Coordinated Proceeding involving thousands of claimants who allege that Zantac, an antacid medication, has carcinogenic properties.
- a putative nationwide class action involving claims that Chapstick products were misleadingly labeled as “100% Natural” and containing “Naturally Sourced Ingredients.”
- Washington Legal Foundation as counsel of record on amicus briefs filed in the U.S. Supreme Court related to product liability cases concerning Rule 702 and the admissibility of expert testimony, and the application of non-mutual, offensive collateral estoppel in multidistrict litigations.