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Mark T. Doerr


Mark Doerr is a Litigation and Intellectual Property partner in the New York office of Greenspoon Marder.  Mark is a litigator who also serves as adviser and outside general counsel to companies and individuals in an array of situations and industries.  He works with businesses and people in highly regulated industries, technology start-ups, financial institutions, and publicly traded companies, among other spaces.

Mark’s main legal practice is evaluating, investigating, litigating, and resolving major disputes. His practice usually involves issues of deceptive practices and fraud, and includes claims of RICO, contract, fraud, and myriad tort claims in federal and state court.  Mark’s practice also regularly regards state and federal Constitutional issues.

Mr. Doerr is also an experienced intellectual property lawyer who counsels and represents clients in matters of trade secrets, trademark infringement prosecution and defense, and other unfair competition-related claims.  He advises and represents businesses and individuals in First Amendment matters, involving false light, rights of publicity, defamation, and other reputational-related issues affecting both subjects of published content and publishers.  Mr. Doerr also advises clients in patent disputes and litigation.

Mr. Doerr has major experience in transnational disputes involving multi-billion-dollar claims and judgments in foreign jurisdictions.  He has represented companies in domestic and foreign investigations, litigations, and arbitrations spanning multiple jurisdictions.  Mr. Doerr has brought and defended numerous Section 1782 actions for discovery relating to disputes in non-U.S. jurisdictions.

Mr. Doerr has conducted and managed investigations in response to regulatory and government civil and criminal inquiries regarding accounting fraud, LIBOR manipulation, securities fraud, healthcare fraud, the Foreign Corrupt Practices Act, and the False Claims Act.

A happy New Yorker, Mark proudly serves New York City.  He is a member of the New York City Bar Association’s New York City affairs committee.  He also provides pro bono legal services to individuals in New York and New Jersey in immigration proceedings.  In addition, he serves as an adviser and legal counsel to the Washington Square Park Conservancy, a 501(c)(3) organization helping New York’s Washington Square Park thrive.  Mark is a member of the New York Intellectual Property Law Association and the New York Volunteer Lawyers for the Arts.  He also serves on the board of directors of the Maya Health Alliance, a 501(c)(3) non-profit that operates medical programs in Guatemala.

Mr. Doerr earned his law degree from Columbia Law School, with honors as a Harlan Fiske Stone Scholar, and was the Articles Editor for the Columbia Human Rights Law Review.  He graduated with a bachelor’s degree in philosophy with distinction from the University of Illinois at Urbana-Champaign and was an Edmund J. James Scholar.

After law school, Mark served as an inaugural law clerk to the Honorable Pamela K. Chen of the United States District Court for the Eastern District of New York.

Mr. Doerr is admitted to practice law in the States of New York and Illinois and federal district and circuit courts around the country.

Bar Admissions

  • New York
  • Illinois

Court Admissions

  • U.S. District Court, Southern District of New York
  • U.S. District Court, Eastern District of New York
  • U.S. District Court, Eastern District of Michigan
  • U.S. District Court, Colorado
  • U.S. District Court, Southern District of Texas
  • U.S. Court of Appeals, Sixth Circuit


  • J.D., with honors, Columbia Law School
    • Harlan Fiske Stone Scholar;
    • Columbia Human Rights Law Review, Articles Editor
  • B.A., with distinction, University of Illinois
    • Philosophy Departmental Honors
    • Dean’s List
    • Edmund J. James Scholar

Professional and Community Involvement

  • New York Intellectual Property Law Association (NYIPLA), Member
    • AI, Cybersecurity & Digital Technologies Committee, Co-Chair, 2023

Speaking Engagements

  • Featured Speaker, “Artificial Intelligence: Where Will AI Take the Law?” New York Intellectual Property Law Association (NYIPLA), May 10, 2023


  • U.S. News and World Report, “Best Lawyers in America: Ones to Watch,” Securities Regulation, 2023-2024
  • Benchmark Litigation, “Under 40 Hot List,” 2022-2023


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