Arnold & Porter Secures Resolution of Investment Treaty Arbitration for the Kingdom of Thailand
Arnold & Porter represented the Kingdom of Thailand in the resolution of a long-running investment treaty arbitration brought by Australia-listed mining company Kingsgate Consolidated Limited and its subsidiary Kingsgate Capital Pty Ltd (collectively, “Kingsgate”), in connection with certain regulatory measures affecting Thailand’s largest gold and silver mine, Chatree. On November 27, 2025, Kingsgate announced that it had agreed to terminate the arbitration without issuance of an award. That termination has now been effectuated, ending nearly eight years of proceedings.
The arbitration was conducted under the UNCITRAL Arbitration Rules and seated in Singapore, with the Permanent Court of Arbitration acting as registry. Kingsgate commenced the arbitration in 2017 under the Australia–Thailand Free Trade Agreement (TAFTA), following Thailand’s imposition in 2016 of a temporary moratorium on all mining activities amid environmental and public health concerns, as well as the adoption of certain regulatory reforms governing mining operations. Kingsgate asserted treaty claims, including alleged breaches of the fair and equitable treatment standard, the most favored nation treatment, and protections against unlawful expropriation. All of those claims have been withdrawn with prejudice, without any admission of liability or payment of compensation by Thailand.
Arnold & Porter partner Anton A. Ware, who acted as lead counsel for Thailand, commented: “We are very pleased with this resolution, which definitively extinguishes all claims asserted against Thailand and enables the parties to focus their energies on productive pursuits.” The case raised important questions concerning States’ sovereign right to regulate in relation to environmental and public health matters and application of the precautionary principle in investment treaty arbitration.
The Arnold & Porter team was led by partner Anton A. Ware and included partners Paolo Di Rosa and Ethan Shenkman, as well as senior associates Tereza Gao and Bart Wasiak.
