The IIA Issues Note reviews developments in investor-State dispute settlement (ISDS) in 2015. It contains the latest numbers on ISDS cases, summaries of selected new cases and an in-depth analysis of arbitral decisions.

Developments in investor-State arbitrations in 2015:

• A record high of 70 ISDS cases were filed in 2015. The overall number of publicly known ISDS claims reached 696.
• By the end of 2015, a total of 444 ISDS proceedings have been concluded, with 36 per cent of cases decided in favour of the State, 26 per cent in favour of the investor and 26 per cent of cases settled.
• Following the recent trend, a high share of new cases in 2015 (about 40 per cent) was brought against developed countries, including many cases by European investors against European Union member States.
• The majority of new cases invoked bilateral investment treaties (BITs), most of them dating back to the 1990s. In about one third of all cases last year foreign investors relied upon the Energy Charter Treaty, which by now is the most frequently invoked treaty (87 cases), followed by the North American Free Trade Agreement (56 cases), and the Argentina–United States BIT (20 cases).
• State conduct that was most frequently challenged by investors in 2015 included legislative reforms in the renewable energy sector, alleged direct expropriations of investments, alleged discriminatory treatment, and revocation or denial of licences or permits.
• Newly filed cases include, among others, claims related to events in Crimea, a mass claim arising out of the Eurozone crisis, a case concerning the prohibition of gaming, a first-ever claim invoking the WTO General Agreement on Trade in Services, and several tax-related disputes.
• In 2015, ISDS tribunals rendered at least 51 decisions, of which 31 are in the public domain. Most of the public decisions on jurisdiction were decided in favour of the State, while the majority of those on merits ended in favour of the investor.
• Arbitral decisions adopted in 2015 touch upon a number of important legal issues concerning the scope of treaty coverage, the conditions for bringing ISDS claims, the meaning of substantive treaty protections, the calculation of compensation and others. On some issues, tribunals followed previous decisions, while on some other issues they adopted approaches that departed from earlier decisions.
• Some of the prominent decisions rendered in 2015 concern investor nationality, ownership and control. This topic – including approaches, implications and policy challenges – receives in-depth coverage in UNCTAD’s World Investment Report 2016 scheduled to be launched on 21 June.