Buried Hill: Arbitrator Disqualified Over Bias Concerns

On 11 February 2026, in Buried Hill v. Turkmenistan, the two remaining arbitrators, Mr Siqueiros and Mr Goldberg (the “Unchallenged Arbitrators”), accepted Buried Hill Serdar Limited’s (the “Claimant”) proposal to disqualify Professor Philippe Sands, KC, from the tribunal. Their decision was based on Articles 14(1), 57 and 58 of the Convention on the Settlement of Investment Disputes Between States and Nationals of Other States (the “ICSID Convention”) and Rule 23(1) of the 2022 ICSID Rules of Procedure for Arbitration Proceedings (the “ICSID Arbitration Rules”).¹

The Decision addresses a recurring problem in international arbitration: whether the same arbitrator can serve in two separate cases involving different legal claims but many of the same facts, witnesses and documents, as well as the same underlying asset. The Unchallenged Arbitrators rejected the idea that parallel appointments are automatically disqualifying. What mattered was the unusually close overlap in witnesses,