LAWYER PROFILE
Michael de Leeuw

Michael de Leeuw

USA 2026

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Ranked in 1 practice area

About

Provided by Cozen O'Connor

USA

Practice Areas

Michael de Leeuw is vice-chair of Cozen O’Connor’s national Business Litigation Group. He is a skilled advocate with a successful track record in courts throughout the United States and in international tribunals. Michael has a diverse practice with deep experience in the areas of appellate law, antitrust, class actions, defamation, securities, and real estate-related litigation.

Michael leads Cozen O’Connor’s appellate practice and is co-chair of the firm’s securities and class action practices. He has represented a broad array of clients in precedent-setting matters before state and federal appellate courts and at the United States Supreme Court.

Michael briefed, argued, and won a case at the United States Supreme Court, Manhattan Community Access Center v. Halleck. In that case, the United States Supreme Court reversed the Second Circuit Court of Appeals and made new law regarding the critical constitutional question of when a private party can be deemed a “state actor” and thus potentially liable for constitutional violations. He has also represented dozens of other parties at the United States Supreme Court, including members of Congress and advocacy organizations from around the country.

Michael also has an active real estate litigation practice, representing lenders, borrowers, owners, REITs, developers, and landlords in all types of real estate-related litigation, particularly litigation relating to distressed assets.

Michael has been appointed an expert witness in cases pending in the Courts in the United Kingdom on issues relating to New York law.

Michael has been consistently recognized by Chambers USA: America’s Leading Lawyers for Business as a leading individual in General Commercial Litigation; and he has been recognized in Super Lawyers as a Top Rated Business Litigation Lawyer for the past eleven years.

Michael is active in civic and professional organizations and has an extensive pro bono practice focusing primarily on voting rights trials and appeals throughout the United States.

Chambers Review

Provided by Chambers

Chambers Guide to the USA

Litigation: General Commercial - New York

Band 4
Band 4

Individual Editorial
Michael de Leeuw is a skilled trial and appellate lawyer with experience handling securities, antitrust and wider commercial matters, with several appearances before the US Supreme Court.

Strengths

Provided by Chambers

  • Michael is an amazing litigator and legal theorist. He is engaged with case law and contemporary legal issues and theory.

    Litigation: General CommercialChambers Guide to the USA
  • Michael is incredibly responsive and knowledgeable.

    Litigation: General CommercialChambers Guide to the USA

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