The team at Dechert handles coordinated MDL and state court mass tort litigation across multiple jurisdictions, including matters alleging that a heartburn medication formed NDMA and caused cancer. The practice is led by Jay Bhimani in Los Angeles, alongside Mark Cheffo and Douglas Fleming in New York, who oversee strategy and coordination in large-scale proceedings. Sheila Birnbaum, also based in New York and recently re-joined after retirement, focuses on claims alleging personal injury or economic loss arising from medication-related crises and regularly serves as national counsel in federal MDLs and parallel state court actions involving significant damages. Cheffo also brings experience as lead defense counsel for GlaxoSmithKline in pharmaceutical litigation, supporting clients through complex discovery, expert challenges, and trial preparation in mass tort disputes.
Legal 500 Editorial commentary
Accolades
Client satisfaction: Lawyer & team quality
Client satisfaction: Sector knowledge
Testimonials
Collated independently by Legal 500 research team.
- 'Deep expertise in mass tort product liability and class actions.'
- 'Mark Cheffo, excellent strategist and skills with communicating with opposing counsel.'
Key clients
- GlaxoSmithKline
- Teva Pharmaceuticals USA, Inc
- Johnson & Johnson
Work highlights
Served as sole counsel to Teva Pharmaceuticals in PFAS water-supply contamination litigation filed in February 2025.
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Practice head
Jay Bhimani; Mark Cheffo; Douglas Fleming
Other key lawyers
Sheila Birnbaum