A Guide to Interim Measures in Investor-State Arbitration

While interim measures have been available to parties in international arbitration for decades, recent years have witnessed an explosion in the number of requests submitted and decided. In the context of investment-treaty arbitration, this boom in interim measures decisions has brought a great diversity of substance, making a comprehensive look at the current state of interim measures both timely and necessary. This article is divided into four remaining sections, designed to appeal to practitioners, parties, and decision-makers alike. The second and third sections look to assist in the proper drafting of an interim measures request and order, by identifying and discussing current developments in the key institutional rules and legal standards. We start by addressing developments in the legal standards underpinning interim measures, which arise from institutional rules and case-law developments and involve some or all of the following factors: (1) urgency in the sense that the risk of harm or prejudice is imminent; (2) a threat of substantial or irreparable harm to rights or property capable of being protected by the tribunal; (3) prima facie jurisdiction over the subject-matter of the request; (4) prima facie establishment of a valid claim on the merits; and (5) the extent to which interim measures would burden the other party. Although the decision whether to grant interim measures is necessarily fact-specific, making a clear synthesis of the case law not always possible, a few threads have emerged in the recent case law, particularly regarding irreparable harm and urgency. Recent developments with respect to these two elements – which arguably contain the most ascertainable legal standards among the five – warrant practitioners’ attention, including the importance of changed circumstances for urgency, and the impact of the form of relief requested ( i.e. , non-monetary or monetary damages) on proving irreparable harm. The third section therefore …