Cyrus Benson is a U.S. and English qualified partner in the London office of Gibson, Dunn & Crutcher and serves as co-chair of the firm’s International Arbitration Practice Group.

Cyrus represents clients from a wide variety of sectors before commercial and investment treaty tribunals with particular experience in telecoms, oil & gas, mining and infrastructure disputes. He continues to represent a Dutch and a Luxembourg investor in two separate multi-billion dollar arbitration proceedings against the Russian Federation under the Energy Charter Treaty.

He is lead advocate for a major international contractor in billion dollar ICC proceedings against a Middle Eastern state arising from an airport project, and spear-headed a team in the successful prosecution of a US$ 2 billion LCIA arbitration for a global mining corporate against a Middle East steel manufacturer. He also continues to represent a Middle Eastern conglomerate in a US$ 500 million ICSID arbitration under the Kuwait/Iraq bilateral investment treaty arising out of an investment in Kurdistan; and a Swedish holding company in a US$ 1.5 billion ICSID arbitration against a North African State for expropriation of a refinery and related businesses.

This past year he successfully defended a European telecommunications company in an ICC arbitration brought by a middle-eastern telecommunications provider arising from a multi-billion euro M&A transaction.

He was a member of the IBA Arbitration Committee Task Force on Ethics for Counsel and served as one of the UK members to the ICC Rules Revision Task Force. He sits regularly as an arbitrator, and writes and lectures on a wide variety of arbitration issues.

He has championed the USAID-backed joint legal reform initiative (with the Mongolian Ministry of Justice) to design and teach a course on international arbitration law and practice (covering both commercial and investment treaty arbitration) to Mongolian lawyers and judges.

Cyrus is ranked as a leading lawyer for International Arbitration in the 2007-2023 Chambers UK guides, who describe him as “he’s superb and has an excellent grasp of strategy. He’s an excellent advocate and first-rate cross-examiner.” In previous editions, he is noted as “an exceptional advocate. He understands the legal issues and the tactics. He is a really effective advocate and cross-examiner” and “a formidable advocate.” He is also ranked in the 2010, 2014-2022 Chambers Global guides, 2021-2022 Chambers Europe guide and in the 2009-2024 editions of Best Lawyers International in the UK. In addition, Legal 500 UK 2023 ranks Cyrus in the Hall of Fame listing for International Arbitration and recognises him for Public International Law as well as recommending Gibson Dunn’s International Arbitration Practice generally (the publications recently cited him as being ‘a class act’ and “an exceptional lawyer and a first-rate advocate among the best-regarded practitioners in the market. He is tactically astute and a strong strategist. He is the lawyer that I would want in my corner).” He is “highly recommended” for Dispute Resolution: Arbitration in Practical Law Company’s Which Lawyer? (2007-2012), is identified by UK Legal Experts 2012 as an expert in the field of Arbitration and recommended in Arbitration in Who’s Who Legal 2023.  He has also been recommended for Dispute Resolution: International Arbitration in Chambers Europe and is ranked as a ‘Litigation Star’ for International Arbitration by Benchmark Litigation Europe 2022. He is also ranked for International Arbitration and Litigation in the Lawdragon 500 Global Litigation Lawyers guide 2021.

Prior to joining Gibson Dunn, Cyrus was co-head of the London International Arbitration Group at a U.S. law firm.