Deborah Renner

Deborah Renner is a Partner in Dentons' Litigation and Dispute Resolution practice, based in New York. Her practice focuses on Commercial Litigation, with a focus on class action defense, financial services litigation and broker-dealer regulatory matters.

Nationally recognised as a leader in class action law, Deborah has defended numerous companies in nationwide and state class actions and multi-district litigation (MDL) spanning numerous areas, including false advertising, consumer fraud, insurance, RESPA, antitrust, securities and data privacy cases. She has represented amici curiae before the US Supreme Court on class action issues and frequently litigates at the appellate level.

Deborah was previously a partner at Sonnenschein, Nath & Rosenthal, a legacy firm of Dentons US. She subsequently was a lead lawyer for the Securities Investor Protection Act (SIPA) trustee in high-profile Madoff litigation. She then worked in the Enforcement Division of the Financial Industry Regulatory Authority (FINRA), where she handled broker-dealer regulatory matters.

Given her wide range of experience in complex, high-stakes litigation and regulatory issues, clients turn to Deborah for her counsel in assessing risk and defending complex matters.

Her experience includes successfully representing numerous retailers in nine putative class actions around the country alleging false advertising with respect to lidocaine products, dismissing or resolving cases without class certification; winning complete dismissal of class action alleging misleading marketing of air fryers; winning complete dismissal of a false advertising class action against a publisher; and representing nutrient supplement companies, publishers, mortgage servicers and hotel chains in various class actions and appeals.

In securities, she successfully led the team representing SIPA Trustee Irving Picard in a bankruptcy adversary proceeding against a major investment bank, resulting in settlements totalling $543 million for the trustee and class members, and forfeiture payments to the US Attorney's Office totalling $1.7 billion. She also successfully represented the SIPA Trustee before the Second Circuit Court of Appeals, enforcing a permanent injunction against litigants in class actions seeking $7 billion.

She has represented amici in the US Supreme Court in Tyson Foods, Inc. v. Bouaphakeo, 136 S. Ct. 1036 (2016); The Standard Fire Ins. Co. v. Knowles, 133 S. Ct. 1345 (2013); and Comcast Corp. v. Behrend, 133 S. Ct. 1426 (2013).

She holds a JD, cum laude, from Harvard Law School, an MA from Princeton University and a BA with general and department honours from Johns Hopkins University. She is listed as a Recognized Lawyer by The Legal 500 (2026) and has been recognised in New York Super Lawyers (2011–2020, 2022–present), including Top 50 Women in NY (2014).