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Diane P Sullivan
Lawyers profile
USA 2026
Lawyers profile | USA 2026: Litigation: Trial Lawyers, Product Liability & Mass Torts, Litigation: Product Liability, Litigation: General Commercial
Diane P Sullivan
Ranked in 4 Practice Areas

Star Individuals

Litigation: Trial Lawyers

USA - Nationwide

13 Years Ranked

1

Band 1

Product Liability & Mass Torts

USA - Nationwide

17 Years Ranked

1

Band 1

Litigation: Product Liability

New Jersey

7 Years Ranked

2

Band 2

Litigation: General Commercial

New Jersey

15 Years Ranked

Ranked in Guides
Global 2026

About

Provided by Diane P Sullivan

USA

Practice Areas

Diane Sullivan is a renowned trial attorney who is routinely retained as lead trial counsel in high-stakes litigations involving “first-of-kind,” “bet-the-company,” or otherwise high-profile matters that have garnered extensive media coverage across a range of practice areas and industries. She has successfully tried cases for Fortune 500 companies in complex commercial, mass tort, class action, antitrust, patent, and environmental litigations in jurisdictions around the U.S. She has represented some of the biggest, most recognizable companies across industries, including Johnson & Johnson, Altria, AstraZeneca, Baxter Healthcare Corporation, Campbell Soup Company, Duke Energy, ESPN, ExxonMobil, Frontier Communications, General Electric, GlaxoSmithKline, Merck, PepsiCo., Philip Morris USA, Procter & Gamble, Repsol, SAC Capital, Sanofi, Toyobo, and Walgreens.

Professional Memberships

New Jersey Bar; New York Bar; DC Bar; admitted to practice before several federal courts.

Personal

Fairfield University (BA, 1984); University of Pennsylvania Law School (JD, 1987).

Chambers Review

Provided by Chambers

Chambers Guide to the USA

Litigation: Trial Lawyers - USA - Nationwide

Star Individuals
Individual Editorial
Diane Sullivan is renowned for her trial work, with particular expertise defending large medical device and pharmaceutical companies in major product liability trials, including high-stakes mass torts. She is based in the New York office at Weil.
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Product Liability & Mass Torts - USA - Nationwide

1
Band 1
Individual Editorial
Diane Sullivan is an esteemed trial lawyer with experience acting as lead counsel on numerous market-leading mass torts. Alongside her experience in representing Fortune 500 companies on nationwide talc litigation, she is also active in environmental and natural resource cases.
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Litigation: Product Liability - New Jersey

1
Band 1
Individual Editorial

Diane Sullivan of Weil, Gotshal & Manges comes highly recommended for her handling of high profile product liability claims and commercial disputes.

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Litigation: General Commercial - New Jersey

2
Band 2
Individual Editorial

Diane Sullivan of Weil, Gotshal & Manges comes highly recommended for her handling of high profile product liability claims and commercial disputes.

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Strengths

Provided by Chambers

Diane is an outstanding trial lawyer.

Litigation: Trial Lawyers respondent
Chambers Guide to the USA

Diane Sullivan is an excellent trial lawyer.

Product Liability & Mass Torts respondent
Chambers Guide to the USA

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