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McNeill, Mark
Direct Tel: +1 212-849-7351, Direct Tel: +1 646-995-9294, Direct Fax: +1 212-849-7100
New York
Tel: +1 212 849 7000 Fax: +1 212 849 7100
Tel: +44 20 7653 2000 Fax: +44 20 7653 2100

Mark McNeill heads the firm’s International Arbitration practice in New York. For over two decades he has acted as advocate in numerous high-value, complex commercial and investment treaty arbitrations, including 14 years based in Europe. He has handled arbitrations under the auspices of all the major arbitration institutions and rules, including the ICC, LCIA, ICSID, SCC, AAA, ICDR, Swiss Chamber of Commerce, UNCITRAL, DIS and LMAA. He also sits as an arbitrator in complex commercial disputes and serves as an expert witness on arbitration issues under New York law.

Mark’s experience spans various subject matters, including oil & gas, joint ventures, post-M&A disputes, construction contracts, pharmaceuticals, intellectual property, technology, nuclear power, taxation, mining & metals, telecommunications, insurance and global enforcement of arbitration awards.

Mark recently obtained an award for a client in an arbitration against the Republic of India for over $1.7 billion (principal and interest). He previously represented shareholders in the former Yukos Oil Company against the Russian Federation in relation to the expropriation of their investment resulting in an award of over $50 billion, the largest arbitral award ever.
Mark previously worked in the Office of the Legal Adviser of the U.S. Department of State where he represented the United States in investor-State arbitrations brought under the North American Free Trade Agreement (NAFTA) and participated in the drafting of US investment treaties.
For the past 10 years, Mark has lectured on international investment arbitration at Sciences Po Law School in Paris.

Mark is triple-qualified, admitted to practice in New York, Paris (avocat à la cour) and England & Wales (solicitor-advocate with Higher Rights of Audience in Civil Proceedings).
Mark is consistently highly rated in the most prominent legal directories in the areas of international arbitration: Legal 500 (2020) notes that "Mark McNeill is absolutely top class, both in his strategic and subject matter advice, but also in his written work and advocacy". Who’s Who Legal (2020) ranks Mr. McNeill as a Thought Leader in International Arbitration and notes that he is "an excellent strategist and great with clients". Chambers & Partners US (2021) notes that "Mark is a great strategist and advocate, and is phenomenal at cross-examination."; "He is a seasoned practitioner and is an excellent lawyer"; "He demonstrates a highly client-focused approach and incredible attention toward winning." Chambers & Partners Global (2020) notes that Mr. McNeill "receives consistently positive feedback", and that clients praise his advocacy skills, stating that he is "very sharp" and is "very talented".


  • United Group
  • Cairn Energy PLC
  • Rasia FZE
  • Areva SA
  • Sanofi SA
  • Solvay SA
  • Alverley Investments Ltd


  • Successfully represented Cairn Energy PLC in an arbitration against the Republic of India.  In December 2020, the arbitral tribunal issued a unanimous decision in Cairn’s favor in the amount of USD 1.7 billion (principal and interest).  The claims were submitted under the UNCITRAL Arbitration Rules and the UK-India Bilateral Investment Treaty, and related to retrospective tax measures adopted by the Indian Government.
  • Alverley Investments Limited and Germen Properties Ltd, Claimants in an ICSID arbitration against Romania (ICSID Case No. ARB/18/30). The dispute relates to a multi-billion euro commercial and residential real estate project in northern Bucharest. The claims are brought under the Cyprus-Romania bilateral investment treaty.
  • Rasia FZE and Joseph K. Borkowski, Claimants in an ICSID arbitration brought against the Republic of Armenia under the U.S.-Armenia bilateral investment treaty and two concession agreements concluded with the State (ICSID Case No. ARB/18/28). The dispute arises out of two concession agreements to develop, maintain and operate both a rail network and a high speed road network in Southern Armenia. Over $260 million is at stake.
  • A French-German consortium, Claimant in an ICC arbitration in Stockholm against a Finnish utility company. The dispute arose from an agreement for the construction of a nuclear power plant in Finland. Finnish law governed and the language of the proceedings was English. Over €6.1 billion was at stake.
  • A U.S. investor in an ICSID arbitration against a CIS State involving railway and road concessions.
  • Electricité de France (EDF), Claimant in a UNCITRAL arbitration against the Republic of Hungary. The dispute arose from termination of the Power Purchase Agreements put in place during the privatization of the electricity sector. The claims were brought under the Energy Charter Treaty.
  • A North American agribusiness company, Respondent in an ICC arbitration initiated by European agribusiness companies. The dispute related to the parties’ rights of use with respect to proprietary biotechnology. French law applied.
  • A European pharmaceutical company, Claimant in an ICC arbitration in Paris against three subsidiaries of a global health care company. The dispute arose from a Manufacturing Right Purchase and License Agreement. French law applied.
  • Three European chemical companies in a series of ICC arbitrations in Paris, Geneva and London against the European subsidiaries of a large North American chemical concern. The disputes arose from a joint venture agreement formed to manufacture a product used for the production of nylon. French law applied.
  • A European aviation company, Claimant in an ICC arbitration in Geneva against a North American parts supplier. The dispute arose out of an agreement for the supply of airplane components. French law applied.
  • The majority shareholders in the former Yukos Oil Company, Claimants in a series of three UNCITRAL arbitrations in The Hague against the Russian Federation in relation to the expropriation of their investment in the company. The claims were brought under the Energy Charter Treaty. The Tribunal ordered the Russian Federation to pay over $50 billion in damages to our clients, the largest award ever rendered by an arbitral tribunal. The Tribunal also ordered the Respondent to reimburse to our clients 75% of the legal fees they had incurred in these proceedings, as well as 100% of the arbitration costs.
  • The United States in several arbitrations under Chapter Eleven of the NAFTA, including Methanex Corp. v. United States of America ($970 million claim challenging California’s regulations banning a gasoline additive); Glamis Gold Ltd. v. United States of America ($50 million claim concerning federal and state actions taken with respect to the claimant’s mining claims); In re Consolidated Softwood Lumber Proceedings (consolidated claims for $500 million challenging U.S. antidumping and countervailing duty measures) Canfor Corp. v. United States of America (claims challenging softwood lumber duties that were consolidated); Tembec Inc. v. United States of America (same); and Terminal Forest Products Ltd. v. United States of America (same).
  • A North American reinsurance intermediary, Respondent and Claimant in multiple ad hoc arbitrations in New York and New Jersey against many international insurance companies. The dispute concerned liability of various parties with respect to obligations arising out of a complex international reinsurance pool arrangement. An award was rendered in favor of our client in the lead case. Other cases were thereafter settled on confidential terms.
  • New York University School of Law
    (J.D., 1998)
    • Journal of International Law & Politics:
      • Editor-in-Chief
  • The Johns Hopkins University
    (M.A., International Law & Economics, 1995)
  • Colgate University
    (B.A., English Language and Literature/Letters, 1989)
  • The State Bar of New York
  • Avocat à la Cour, Paris
  • Solicitor, England and Wales (with Higher Rights of Audience)
  • United States Court of Appeals:
    • Second Circuit
  • United States District Court:
    • Southern District of New York
    • Eastern District of New York
  • Japanese
  • French
  • Shearman & Sterling:
    • Partner, 2010-2019
    • Counsel, 2007-2009
  • Office of the Legal Adviser – United States Department of State:
    • Attorney-Adviser, , International Claims and Investments Disputes, 2003-2006
  • International Arbitration and the Rule of Law: Essays in honour of Mr Fali S Nariman: International Commercial Arbitration in India: Some Reflections on Practice and Policy (January 2021)
  • “The Energy Charter Treaty,” in Arbitration under International Investment Agreements: A Guide to the Key Issues 31 (K. Yannaca-Small ed., OUP, 2nd ed. 2018) (with E. Gaillard)
  • “Investor-State Arbitration: Striking a Balance Between Investor Protections and States’ Regulatory Imperatives,” in Contemporary Issues in International Arbitration and Mediation – The Fordham Papers2013, at 270 (A.W. Rovine ed., 2014)
  • “The Doctrine of Separability and Consent to Arbitrate,” 24(3) Arbitration International 475 (2008) (with B. Juratowitch)
  • “ICSID and Investor-State Arbitration Under Fire: The Rejection by Latin American States,” International Bar Association, Section of International Law, International Investment and Development Committee Newsletter, Vol. 1, Issue 1, at 3 (2008) (with M.N. Hodgson)
  • Lecturer, International Investment Law, Sciences Po Law School
  • Faculty, Chartered Institute of Arbitrators (CIArb)
  • Panel of Distinguished Neutrals, CPR Institute for Dispute Resolution
  • Fellow, American Bar Foundation (ABF)
  • Advisory Board Member, Institute for Transnational Arbitration (ITA)
  • Member, CPR European Advisory Board
  • Member, British Institute of International and Comparative Law (BIICL) Investment Treaty Forum
  • Member, American Society of International Law (ASIL)
  • Member, London Court of International Arbitration (LCIA)
  • Member, International Arbitration Institute (IAI)
  • Member, International Bar Association (IBA)