EU Law in investment arbitration: a view from international arbitral tribunals

The conflict between international investment law and EU law provides fruitful insights into how the arbitral tribunals, acting outside the EU’s judicial system, have viewed the EU and EU law. Taking as an example the topical questions of the principle of autonomy of EU law as well as the EU’s State aid rules in investor-State arbitration, the article discusses how arbitral tribunals have seen the role of EU law and how they have treated the opposite demands from the two legal regimes. The claim of EU law rendering the intra-EU investment treaties invalid has constantly proved unsuccessful, and the tribunals have maintained their jurisdiction to be based on international law. However, the possibility of EU law affecting the assessment of the merits of the cases is clearer and more accepted. While harmonious interpretation could somewhat alleviate the remaining conflicts between the two legal regimes, it is unlikely that either regime would compromise the core elements of their systems. The article argues that, for the specific nature of the EU’s legal order to be secured in a way that does not conflict with international law, the relationship between EU law, international (investment) law and investment dispute settlement should be clearly regulated in instruments of international law.