International Investment Arbitration

International investment arbitration is heterogeneous. At its core, it represents the settlement of international investment disputes between foreign investors and host States by arbitration. However, as there are different ways to institute arbitral proceedings, the structural and substantive aspects of international investment arbitration are colored by the mode of commencement of arbitration. An early iteration of international investment arbitration was the submission of investment claims to Mixed Claims Commissions. These had been established by a series of bilateral conventions concluded between the mid-1800s and the early 1900s in order to adjudicate disputes between the nationals of a party State to the convention and the other party State. The types of disputes that fell within the jurisdiction of a Commission were specified in the conventions and varied, depending upon which convention was invoked. This form of international investment arbitration never achieved great prominence because of the small number of investment claims heard but they were a useful source of early jurisprudence and the basic form has continued to be employed in various guises, most notably in the case of the subsequent Iran-US Claims Tribunal. In the early 21st century, however, the two dominant iterations of international investment arbitration are contractually based investment arbitration and treaty-based investment arbitration. In investment contract arbitration, the legal basis for the arbitration is an arbitration clause in a contract which is binding on all contracting parties. In investment treaty arbitration, however, the legal basis for arbitration is a binding offer in a treaty clause by a host State to arbitrate with all protected investors, which any protected investor is then free to accept or reject. For this reason, the latter has been referred to, sometimes derisively, as “arbitration without privity,” a phrase coined by Jan Paulsson. There is also a third category of consent to investment arbitration by acceptance of a unilateral offer of a State through domestic investment laws. Having said that, many investment treaties also record an agreement between the Contracting States to arbitrate disputes arising from the interpretation or application of the treaty. In sum, investment treaty arbitration encompasses investor-State arbitration, which may have a variety of legal bases, and also State-to-State arbitration.