Overview

Admitted to the Paris bar and the Supreme Court of Queensland (Australia), William Ahern is an associate in the International Arbitration practice of the Paris office.

He has acted as counsel for states, investors and companies in over a dozen international arbitrations conducted under the ICSID, ICC, UNCITRAL, LMAA and SIAC rules.

William has particular experience in investor-State disputes, having acted as counsel in over 10 investor-state arbitrations involving parties from Europe, Africa, Asia, North America and the Middle East and spanning a wide variety of sectors. He has also advised numerous clients on investment treaty protection and potential investor-state disputes and written a number of published book chapters and articles on this area of law.

William also has experience in advising in the enforcement of international arbitration awards before domestic courts.

Prior to joining Mayer Brown, William clerked for a Judge of the Federal Circuit Court of Australia and trained and qualified as lawyer in the litigation department of a large Australian commercial law firm.

In addition to his native English, William is fluent in French.

Spoken Languages

  • English
  • French

Experience

Investor-State Arbitration 

  • The Arab Republic of Egypt as respondent in an ICSID Arbitration initiated by a French multinational corporation with respect to a waste management services contract in a major Egyptian city (ICSID Case No. ARB/12/15)
  • Kuwaiti investors in an ICSID Arbitration against the Hashemite Kingdom of Jordan in a dispute related to the tax treatment of their investment (ICSID Case No. ARB/13/38)
  • A US investor and his US companies in an ICSID Arbitration against the Republic of Romania in a dispute related to the expropriation and treatment of their investments in the press distribution and real estate sectors (ICSID Case No. ARB/10/13)
  • The Kingdom of Morocco in an ICSID Arbitration initiated by a European investor in the scrap metal industry (ICSID Case No. ARB/19/2)
  • A Middle Eastern company in a PCA administered UNCITRAL investor-state arbitration against a North African State relating to major construction projects in that country
  • A South Asian company in a UNCITRAL investor-state arbitration against a North African State relating to major construction projects in that country
  • A French multinational corporation in ICSID Conciliation and Arbitration proceedings against a West African State
  • The Republic of The Gambia in an ICSID annulment proceedings before an ad hoc Committee in a case arising from the termination of a mining license in that country including (ICSID Case No. ARB/09/19)
  • The Republic of the Gambia in an ICSID Arbitration against Swedish and Australian investors in a dispute related to a farming enterprise
  • A West African state in an investor-state dispute against a European company in Stockholm Chamber of Commerce proceedings involving an emergency arbitrator

Commercial Arbitration

  • A West African state in arbitration proceedings conducted under the Rules of the London Maritime Arbitrators Association in a dispute involving its European partner (and its Pacific Islands entity) in a Joint Venture agreement for transportation services
  • A French information technology company in a dispute against an Asian entertainment media company under a contract providing for SIAC arbitration
  • A Middle-Eastern company against an North East Asian company in SIAC arbitration proceedings concerning a breach of contract in relation to the health sector in a Middle Eastern country
  • A Lebanese company in an ICC arbitration against a Dutch company concerning an intellectual property license agreement applicable in the Middle East, where the restitution of trademarks is sought
  •  A Middle Eastern party against an Asian company in a pending ICC arbitration with respect to outstanding legal fees
  • A Middle Eastern food company in an ICC Arbitration against its Middle Eastern partner over the breach of their Joint Venture Agreement

Education

Université Jean Moulin Lyon 3, LLM International and European Law (with honours)

College of Law, Brisbane, Australia, Graduate Diploma of Legal Practice

Queensland University of Technology, Bachelor of Laws

Queensland University of Technology, Bachelor of International Business

Admissions

  • Paris
  • Australia, Queensland