The investor-State dispute settlement (ISDS) mechanism provided by Art. 26 (2) (c) of the Energy Charter Treaty (ECT) is highly relevant to the protection of intra-EU investments.1)In 2018, about 45 per cent of all treaty-based intra-EU investment arbitrations were brought pursuant to the ECT. See UNCTAD, Fact Sheet on Intra-European Union Investor-State Arbitration Cases, IIA…