ABSTRACT

While a Non-Disputing Contracting Party (‘NDCP’) does not directly participate in an investment arbitration, its intention is nonetheless pivotal to interpreting the investment treaty into which it enters in the context of general international law and the law of treaties. This is especially true in an investment dispute where the provisions of the treaty at issue appear ambiguous and other evidences fall short of clarifying the contracting parties’ common intention. When and in what form the NDCP expresses its intention of concluding the treaty influence how this opinion may be factored into the consideration of an arbitral tribunal in an investment dispute. All these issues have been touched upon by a series of proceedings of Sanum v. Laos, where China, as the NDCP of the case, expressed its opinion on the territorial application of the China-Laos BIT through diplomatic letters and subsequent statements. This chapter will first take a closer look at the arbitral award and two judicial decisions of the case, with a focus on the exchange of letters between Laos and China in relation to China’s position of the PRC-Laos BIT’s territorial application. Then, it will further scrutinise the approaches that the tribunal and two Singaporean courts adopted in relation to China’s expression of opinion in Sanum v. Laos and analyse what factors have been weighed in in terms of ascertaining the common intention of the contracting parties to the treaty in an investment arbitration. Lastly, it observes that the timing, the forms and the deference should be considered by an NDCP when giving its opinion on the intention of a treaty if it attempts to maintain the consistency between the tribunal’s interpretation consistent with the contracting parties’ common intention.