The European Union’s (EU’s) withdrawal from the Energy Charter Treaty (ECT) has highlighted the tension between investment protection and energy transition. Originally conceived to secure energy investments, the ECT’s investor-state dispute settlement (ISDS) mechanism has increasingly been invoked to challenge legitimate climate policies, thereby threatening the EU’s regulatory autonomy in pursuing decarbonization. This tension is particularly evident in the operation of Article 47(3) of the ECT, whose continued application, even under the ECT’s proposed modernization, which merely reduced protection for fossil fuel investments from twenty to ten years, was ultimately deemed insufficient by the EU to reconcile the ECT with its climate obligations, prompting withdrawal rather than partial reform. This article explores the legal and policy implications of this clause post-withdrawal. Through the analytical lens of prominent fossil fuel claims, it highlights the ongoing legal risks EU Member States face when adopting climate measures that disrupt existing fossil fuel energy investments. These cases illustrate the risk of regulatory chill and the potential surge in fossil fuel-related disputes deployed to resist the EU’s energy transition. In response, this article proposes a framework of doctrinal and procedural reforms aimed at neutralizing these tensions. Two conceptual pillars: (1) Doctrinal Leverage and Strategic Risk Management and (2) Institutional Transparency and Procedural Innovation offer integrated legal, institutional, and normative tools to reclaim regulatory space for a just transition. The article ultimately advocates for a transformed investment regime attuned to global sustainability imperatives.
European Investment Law and Arbitration Review