Mr Mark S. Cheffo > Dechert LLP > New York, > Lawyer Profile

Dechert LLP
Three Bryant Park, 1095 Avenue of the Americas
NEW YORK, NY 10036-6797
Mark S. Cheffo photo

Work Department

Product Liability and Mass Torts


Mark S. Cheffo is co-chair of Dechert’s product liability and mass torts practice and has extensive experience serving as national coordinating and trial counsel in complex product liability, insurance and mass torts litigation. He acts for corporates and individuals in the pharmaceutical, medical device manufacturing, bioengineering, insurance and industrial products industries, amongst others. Mr. Cheffo has also handled numerous toxic and environmental exposure suits.

Mr. Cheffo has taken part in several trial teams in high-profile pharmaceutical litigation, managing all stages of a dispute from negotiation, through pre-trail proceedings to trial. In addition to defending expert and company witness depositions, Mr. Cheffo has briefed and conducted numerous Daubert and Frye challenges. He has also briefed and argued dispositive motions and appeals in state and federal courts throughout the United States. Mr. Cheffo also has considerable experience conducting arbitrations and mediations relating to disputes.


New York City Bar Association; International Association of Defense Counsel


Stony Brook University, B.A., with Honors, 1987, Pi Sigma Alpha National Political Science Honor Society, Phi Alpha Theta International History Honor Society; Boston University School of Law, J.D., 1990, Editor-in-Chief of American Journal of Law & Medicine, Paul J. Liacos Scholar

Lawyer Rankings

United States > Dispute resolution > Leading trial lawyers

(Leading trial lawyers)

Mark S. CheffoDechert LLP

United States > Dispute resolution > Product liability, mass tort and class action - defense: pharmaceuticals and medical devices

(Leading lawyers)

Mark S. CheffoDechert LLP

Drawing upon a strong pool of experienced and up-and-coming talent on the East and West coasts, in particular, Dechert LLP is able to handle a wide variety and volume of defense matters for many leading pharma and medical devices clients, particularly in the context of large-scale MDLs/class actions. The firm regularly takes the lead role in such aggregated mandates, formulating core strategy decisions and regularly securing key victories through persuasive motions, as well as in litigation before juries. Mark Cheffo is regularly at the forefront of the highest-profile mandates handled by the firm, a reflection of the esteem with which he is held by clients as a result of his expertise through the litigation process, including at a motions stage – where he has briefed and conducted numerous Daubert/Frye challenges. Lauded as a ‘strong practitioner with excellent strategic smarts’, Los Angeles-based partner Kimberly Branscome is a key exemplar of the firm’s trial expertise, in particular, as well as its visibility throughout California. The vastly experienced Sheila L. Birnbaum  has amassed many successes at trial and motions stage throughout her long career and has had involvement in many key medical devices/pharmaceutical product liability matters, including as it relates to opioid medication, breast implants and mesh products. Cheffo, Branscome and Birnbaum co-head the team that also includes Paul LaFata, who has developed niche expertise in relation to the co-ordination of multi-jurisdictional elements of major product liability MDLs and class actions and Rachel Passaretti-Wu, who as well as her versatile core pharma and toxic tort litigation offering, is also adept at assisting clients with appropriate crisis management-related responses. All named practitioners are based out New York, unless otherwise stated.

United States > Dispute resolution > Product liability, mass tort and class action - defense: toxic tort

Primarily centred out of New York but also gaining traction on the West Coast, exemplified by the work of Los Angeles based Kimberly Branscome, Dechert LLP regularly handles high-profile toxic tort-related class actions and MDLs, both in the environmental space, as well as in cases involving harm caused by pharma products. In these matters the team, which includes many accomplished trial lawyers, regularly acts as national counsel, coordinating and presenting the key arguments and motions to the courts. Douglas Fleming has a strong grounding in environmental toxic torts and is a key member of the team alongside Rachel Passaretti-Wu defending  Saint-Gobain in high-profile civil litigation and regulatory matters relating to alleged damage caused by exposure to forever chemicals in drinking water. An expert in toxic torts, Sheila L. Birnbaum  has deep expertise in the space and co-heads the overarching product liability and mass torts team alongside Branscome and Mark Cheffo . All named practitioners are based in New York, unless otherwise noted.

United States > Dispute resolution > Product liability, mass tort and class action - defense: consumer products (including tobacco)

Primarily based in New York and California, Dechert LLP‘s product liability and mass torts team has a strong reputation, in particular, in the defense of consumer product-related healthcare and pharma matters. As well as handling many high-profile consolidated disputes relating to personal injury as a result of side effects following the use of drugs manufactured from brand-name pharma companies, the team also handles a growing number of healthtech-related disputes. In this regard, Los Angeles-based Benjamin Sadun is representing a well-known women’s health app in its global defense of alleged privacy violations. Outside of the healthcare and pharma space, the firm continues to defend 3M in the largest ever MDL to date brought by  US military veterans and service members alleging that their hearing loss was caused by defective earplugs sold to the US military. Los Angeles-based partner Sheila Birnbaum co-heads the overarching product liability and mass torts group alongside Mark S. Cheffo  in New York. Former co-head Kimberly Branscome moved to Paul, Weiss, Rifkind, Wharton & Garrison LLP in February 2024.