Mr. Greenfield is a highly regarded civil litigator who focuses his practice on securities and shareholder disputes, FinTech and digital asset litigation, consumer class actions, mergers and acquisitions litigation and complex commercial disputes. Mr. Greenfield is recognized in the areas of Securities Litigation Defense and General Commercial Disputes by The Legal 500 US (2023), where he has been praised as “brilliant” and “incredibly strategic,” with one client commending him as “the best legal writer I have ever worked with.” He is also ranked as a leading lawyer for Crypto-Asset Disputes by Chambers FinTech (2024), where clients praise him as “a smart tactician” who “understands the space well.” Lawdragon recognizes him as one of the 500 leading litigators in America.

An aggressive, strategic litigator focused on winning cases at the earliest possible stage, Mr. Greenfield helps clients avoid the costs and burdens of protracted litigation. He has an extraordinary track record of victories at the pleading stage, recently achieving dismissals in securities class actions and derivative lawsuits for clients including VMware, Robinhood Markets, Tribune Media Company, Clayton Dubilier & Rice, PPG Industries, NRG Yield, Syncora Guarantee, and the former CFO of Hertz.

Mr. Greenfield is also a leading litigator in the growing FinTech and crypto space, representing clients in high stakes class actions and commercial disputes, including Bitfinex/Tether, Uniswap Labs, Robinhood Markets and Hypersphere Ventures. Mr. Greenfield recently achieved dismissals at the pleading stage in high-profile class action lawsuits against Uniswap and Bitfinex/Tether.

Mr. Greenfield also has substantial experience in corporate governance and mergers and acquisitions litigation, achieving favorable outcomes for a broad range of clients, including Tribune Media Company in its lawsuit against Sinclair Broadcast Group in connection with a failed $3.9 billion merger, the Special Committee of Dell in the dismissal of stockholder class actions challenging a $25 billion going-private transaction, and Providence Equity Partners in winning summary judgment (affirmed by the Delaware Supreme Court) in a stockholder class action challenging a $1.9 billion acquisition.

Having earned a Ph.D. in physics prior to attending law school, Mr. Greenfield combines rigorous legal analysis with a deep understanding of the quantitative and technical aspects of each case, an expertise he brings to bear in challenging damages methodologies and expert testimony. Clients quoted in The Legal 500 cite his unique ability “to understand complex damages analyses at a depth that other attorneys are not” and “to break down and communicate these complicated analyses into simpler terms.”

Mr. Greenfield clerked for the Hon. Victor Marrero in the Southern District of New York. He received a J.D. from New York University School of Law, where he was a Robert McKay Scholar, a Ph.D. in physics from the University of California at Berkeley, and a B.A. from Wesleyan University.

Mr. Greenfield is a member of the Bar of New York and is admitted to practice in the Southern District of New York, the Eastern District of New York and the Second, Third, Seventh and Eleventh Circuit Courts of Appeals.


  • New York University School of Law, 2005, J.D.
  • University of California at Berkeley, 2001, Ph.D.
  • Wesleyan University, 1994, B.A.

Bar Admissions

  • New York