Colahan, John D.

John D. Colahan

Retired Partner

John Colahan retired from the partnership in December 2020. He was based in Latham & Watkins' London office and divided his time with the Brussels office.

He was a member of the Global Antitrust & Competition Practice, having previously been a Legal Advisor at the UK Cabinet Office and international competition law counsel at The Coca-Cola Company. John represented clients before the European Commission, national authorities in Europe and internationally, and conducted litigation in the European courts and numerous national courts. He has advised on a variety of international antitrust matters, including structuring and implementation of international mergers, acquisitions, and joint ventures; cartel enforcement; single firm conduct; and compliance counselling. As a Cabinet Office Legal Advisor to the European Secretariat, Mr. Colahan was responsible for policy coordination with the Treasury and other departments on financial services.    

At the time of his retirement, Mr. Colahan regularly lectured on a range of international antitrust and compliance issues.


  • Postgraduate Diploma in EU Competition Law, King's College London, 1998
  • LSF, College of Law, Guildford, 1990
  • Standard Graduate Officer Course, Royal Military Academy Sandhurst, 1986
  • LLB, University of Nottingham, 1985