Patterson Belknap Webb & Tyler LLP

Litigation; Advertising Litigation

Steve Zalesin is a nationally renowned trial lawyer with extensive experience in advertising litigation, intellectual property, and complex commercial matters. He has successfully tried cases and argued appeals in numerous courts throughout the United States.

For more than 30 years, Mr. Zalesin has represented the nation’s leading consumer products companies in a series of precedent-setting cases that have shaped the landscape of advertising litigation, while helping to preserve and grow the markets for our clients’ products. Among other noteworthy victories, he has won dismissal of several high-profile “greenwashing” cases, in which our clients were accused of misrepresenting the environmental impact of their operations. In addition, he has successfully defended multiple clients in putative class actions that alleged that their products contained dangerous contaminants.  Mr. Zalesin is currently defending major beverage, consumer healthcare, and confectionary companies in litigation over their product labeling and advertising.

Earlier this year, Mr. Zalesin achieved a significant victory for a major pharmaceutical company in a Lanham Act suit brought by a competitor over a study comparing the efficacy of the parties’ prostate cancer medications. The court ruled that the study, which found that our client’s medication is associated with a 51% reduction of overall risk of death compared to the competitor’s drug, employed “reliable” and “widely-accepted” scientific methods and data sources. The court therefore denied the requested injunction. Mr. Zalesin was named “Litigator of the Week” by The American Lawyer for his work on the case (April 24, 2026). The prior month, he obtained summary judgment dismissing a public nuisance suit on behalf of the world’s leading beverage company, for which he was featured in The American Lawyer’s “Litigator of the Week” column (March 20, 2026).

Mr. Zalesin is also known for having secured a federal jury verdict in a landmark dispute over juice labeling. He initially obtained summary judgment dismissing the claims against our client, and successfully defended that ruling before the Ninth Circuit. The U.S. Supreme Court then vacated the Ninth Circuit’s decision and remanded the case for trial. The Los Angeles jury rejected the competitor’s claims in full, returning a verdict in our client’s favor after a six-day trial and less than a day of deliberation. As a result, Mr. Zalesin was named “Litigator of the Week” by The American Lawyer (March 24, 2016).

Mr. Zalesin also maintains an active pro bono practice. In 2020, he obtained a noteworthy dismissal of a class action complaint that targeted a leading online petitioning platform and its efforts to promote racial justice following the murder of George Floyd.

Admitted in: U.S. Supreme Court; U.S. Court of Appeals, First Circuit; Second Circuit; Third Circuit; Seventh Circuit; Eighth Circuit; Ninth Circuit; Federal Circuit; D.C. Circuit; U.S. District Court, Southern and Eastern Districts of New York; Eastern District of Wisconsin; Northern District of Florida; New York

Fellow, the American Bar Foundation (2023-present)

J.D., 1985, University of Pennsylvania Carey Law School (cum laude, Editor, University of Pennsylvania Law Review); B.S., 1982, Syracuse University, S.I. Newhouse School of Public Communications (magna cum laude)