David Gringer

David Gringer is an accomplished trial lawyer with demonstrated success in complex antitrust and false advertising litigation under both state and federal UDAP laws. In the antitrust space, Mr. Gringer is one of the very few attorneys to have successfully tried cases under section 7 of the Clayton Act for both plaintiffs and defendants, and has recently prevailed at trial in different cases brought by the Attorneys General of 16 different states. In 2020, Mr. Gringer was named a “rising star” by Law360 for his experience with “massive cases on both sides of the courtroom.” Drawing on his experience as a trial attorney in the Antitrust Division of the US Department of Justice (DOJ), Mr. Gringer also routinely advises clients responding to government investigations at the state and federal levels. Whatever the legal problem, Mr. Gringer understands that effective representation depends on having a full understanding of the industry at issue.

At the DOJ, Mr. Gringer played a leading role in many of the Antitrust Division's highest-profile matters, including serving as a member of the division's winning trial teams in U.S. v. H&R Block—the division's first successful challenge to a merger in more than eight years—the e-books price-fixing litigation, and writing the division's litigation complaints in U.S. v. Anheuser-Busch and U.S. v. U.S. Airways.

In 2013, Mr. Gringer was selected for an individual Assistant Attorney General Award of Distinction for his work on U.S. v. H&R Block, U.S. v. BlueCross Blue Shield of Michigan, and the proposed and later abandoned 3M/Avery merger, among others.

David has also successfully represented clients at trial in false advertising litigation and mass arbitrations against State Attorneys General, claimants and private class plaintiffs; and in investigations by multistate groups of Attorneys General and the Bureau of Consumer Protection at the FTC. He also routinely advises clients on compliance with state and federal UDAP laws, bringing a trial lawyer’s perspective to these questions.

Before joining the DOJ, Mr. Gringer served as a law clerk to the Honorable Michael Boudin of the US Court of Appeals for the First Circuit. He also has substantial political campaign management experience. In 2005, he was campaign manager for the successful Manhattan Borough president campaign of Scott Stringer, who now serves as New York City comptroller.


    • Won a resounding victory as part of a trial team for clients T-Mobile and Deutsche Telekom in a landmark antitrust trial in which attorneys general from 13 states and the District of Columbia sought to enjoin the merger of T-Mobile and Sprint.
    • Won a complete dismissal of antitrust lawsuit alleging monopolization against a large public utility.
    • Represented Comcast at trial in false advertising litigation brought by the Washington Attorney General alleging violations of the state’s Consumer Protection Act. Successfully prevailed on summary judgment on one of the state’s claims and prevailed on a “half-time” motion to substantially curtail the scope of the remaining claims. Comcast prevailed at trial on the entirety of the state’s initial lawsuit. 
    • Represents a technology company in putative class actions lawsuit alleging unlawful monopolization in the Northern District of California.
    • Advised manufacturers of isopropyl alcohol, petroleum products and other essential commodities with compliance with the price gouging and related laws in all 50 states in response to COVID-19 pandemic.
    • Secured a dismissal of all antitrust damage claims and claims brought under Section 1 of the Sherman Act on behalf of a public utility.
    • Secured the dismissal of a lawsuit alleging orchestrated hacking of computer systems.
    • Secured clearance from the DOJ after the issuance of a Second Request in a major transaction in the data network industry.
    • Represents an online software company in litigation brought by the Los Angeles City Attorney under UCL and Santa Clara County Counsel under the FAL and in several different State AG investigations.
    • Represented a client in connection with antitrust agency and congressional investigations.
    • Represents an online software company in Federal Trade Commission and State Attorney General investigations.
    • Represented the indenture trustee for, and holders of, billions of dollars in bonds in the successful prosecution and appeal of “make whole” and related claims totaling approximately $600 million in the Energy Future Intermediate Holdings Company Chapter 11 case.
    • Represented a large financial institution in an internal investigation related to a technology outage and threatened litigation against the responsible vendor; matter resulted in full indemnification for the client. 
    • Represented a foreign government in federal district court on issues involving the Foreign Sovereign Immunities Act.


  • Named a 2020 “rising star” by Law360 for his experience with “massive cases on both sides of the courtroom”  
  • Recipient of 2020 Burton Award for legal writing
  • Recipient of Assistant Attorney General Antitrust Awards of Distinction in 2010, 2011, 2012 and 2013

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  • Education

    • JD, Columbia Law School, 2008

      James Kent Scholar (2006-2008); Articles Editor, Columbia Law Review; Finalist, Stone Honors Moot Court Competition; Alexander Hamilton Fellow
    • BA, History, University of Pennsylvania, 2003

      summa cum laude
  • Admissions

    • District of Columbia

    • New York

  • Clerkships

    • The Hon. Michael Boudin, US Court of Appeals for the First Circuit, 2008 - 2009