Dawn of a new era? The UNCITRAL rules and UN convention on transparency in treaty-based investor-State arbitration

This article considers how the UNCITRAL Rules on Transparency and UN Convention on Transparency alter the structure of international investment arbitration, as well as its relationship with other regimes of international law. The article provides an overview of how transparency was regulated prior to the advent of the Rules and Convention, their structure and coverage, and their impact thus far (Section II). The article then considers their implications. Section III illustrates how the Rules and Convention effect a fragmentation of international arbitration through their distinction between investment treaty arbitration and other forms of arbitration. That Section furthermore highlights how the Rules and Convention reflect, and may prompt, a growing convergence of investment treaty arbitration and how they promote its linkage to other regimes of public international law. Section IV considers how the Rules and Convention modify the underlying structure of investment treaty arbitration, controlling disputing party and arbitral discretion to shift the structure of arbitration from a private form of dispute settlement to a more public form that takes into account external interests and participants. Section V examines the motivations prompting the development of the Rules and Convention, highlighting their development as a source of legitimacy and acceptance of the investment treaty arbitration regime. That Section highlights the promise of the Rules and Convention and their potential pitfalls, before canvassing a number of topics for future empirical study.