Dual nationality revisited: a modern approach to dual nationals in non-ICSID arbitrations

Abstract

Abstract The authors revisit the vexed question of the standing of investors to bring a claim against one of their states of origin. Contrary to Article 25 of the Convention on the Settlement of Investment Disputes between States and Nationals of Other States (ICSID Convention), which forbids natural persons in possession of the nationality of the host state to initiate proceedings against it, the majority of other arbitration rules do not provide for such a prohibition. Consequently, unlike the realm of diplomatic protection, where the question seems settled, there is little guidance in the treaty-based field of investment arbitration on the probable scenario of a dual national suing one of its states of nationality in a non-ICSID arbitration context. Some tribunals have resorted to traditional principles to deny investment protection to dual nationals, whereas recent awards have been considerably more lenient. This article will demonstrate that, given the fundamental differences between investment treaty arbitration and diplomatic protection, the application by analogy of doctrinal formulations of the former to the latter is not warranted. Instead, a holistic interpretation in accordance with Article 31 of the Vienna Convention on the Law of Treaties should be the primary point of focus of international tribunals, taking into account the object and purpose of the treaty and comparable treaty practice.