Mark Weiner is an experienced trial lawyer whose practice focuses on complex commercial disputes and public interest litigation.
Since joining the firm, Weiner has litigated cases involving antitrust, securities and class action matters. Weiner serves as Head of Litigation for the firm’s Center to Combat Hate.
Weiner’s extensive civil litigation experience includes matters concerning privacy and technology, successfully challenging the implementation of a law requiring the disclosure of troves of customer data on behalf of a global transportation company. He has previously successfully represented a global law firm in a multi-jurisdictional civil RICO action, coordinating with counsel in the U.K. and throughout the U.S. in a multi-faceted defense. Weiner has successfully tried cases through verdict in both federal and state courts across the country, including a defense of a CEO charged with fraud in federal court in a seven-week criminal trial that resulted in dismissal of most of the charges, with the remaining charges dismissed after a successful appeal to the Ninth Circuit.
Lawdragon Honors
| Honor | Year | Practice |
|---|---|---|
| The 2025 Lawdragon 500 X – The Next Generation | 2025 | Complex Civil Litigation |
| The 2024 Lawdragon 500 X – The Next Generation | 2024 | Complex Civil, White Collar, Public Interest Litigation |
Weiner joined the firm from Hecker Fink LLP, where his broad litigation practice included complex commercial litigation, investigations and white collar criminal work.
Weiner previously served as Senior Litigation Counsel at Everytown for Gun Safety. At Everytown, Weiner represented cities and individuals in both plaintiff and defense-side litigation related to gun violence prevention across the country. He represented the City of Albuquerque, New Mexico in a successful defense of its gun violence prevention laws, as well as the Cities of Columbus and Dayton, Ohio in an affirmative challenge to Ohio’s deficient background check system. He also successfully represented an individual victim of a school shooting in a first-of-its-kind challenge to the ‘ghost gun’ industry.
Weiner also served as a trial attorney at The Legal Aid Society of New York. He led the successful defense in multiple trials, both jury and bench, of indigent New Yorkers. Previously, he clerked for the Honorable Susan Y. Illston of the United States District Court for the Northern District of California.
Weiner received his J.D., magna cum laude, from New York University School of Law, where he was a member of the Moot Court Board. Weiner was also a member of the Order of the Coif, a member of the Order of Barristers, and a Root-Tilden-Kern Lindemann Scholar. He received his B.A. from Columbia University.