David Marcus has more than 30 years of experience as a trial lawyer, both in private practice and as a government prosecutor. He has tried cases involving fraud, breach of contract, patent infringement and antitrust.

Mr. Marcus represents clients in patent suits in federal courts across the country. In 2014 and in 2015, he was named by the Daily Journal as one of the "Top 75 Litigators of Intellectual Property" in California.

In addition to patent cases, Mr. Marcus has litigated and tried commercial cases in numerous state and federal courts, including Los Angeles County Superior Court. He also represents companies and individuals in criminal investigations by the United States Department of Justice, and has conducted internal investigations for public companies.

From 1994 to 1998, Mr. Marcus was an Assistant United States Attorney in Los Angeles, where he was a member of the Major Frauds Section. He investigated and tried cases ranging from securities fraud and political corruption to narcotics. From 1999 to 2000, he was the Executive Assistant United States Attorney, responsible for the management of the 240-lawyer office. From 1992 to 1994, Mr. Marcus was an Assistant Attorney General in Massachusetts, where he tried dozens of cases.

Community Involvement

Mr. Marcus serves on the Board of Directors of the American Technion Society.


  • Named to the Daily Journal's 2014 and 2015 lists of California's Top 75 Litigators of Intellectual Property
  • Recognized as a "California Super Lawyer" in 2009–2021 for his general litigation, intellectual property litigation and antitrust litigation practices

Insights & News


  • Education

    • JD, Yale Law School, 1985

      Editor, Yale Law Journal
    • BA, Colby College, 1982

      summa cum laude
  • Admissions

    • California

    • Massachusetts

    • New York

    • US Supreme Court

  • Clerkships

    • The Hon. Mariana R. Pfaelzer, US District Court for the Central District of California



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