Energy Charter Treaty Article 26

Energy Charter Treaty Article 26 is the investor-state dispute settlement provision of the 1994 Energy Charter Treaty, permitting foreign investors in the energy sector to bring arbitration claims against host states for alleged treaty breaches. In the 29 April 2026 EU infringements package, the European Commission issued a reasoned opinion against Hungary over MOL's use of Article 26 to pursue investor-state arbitration against an EU member state — the second infringement in the same package to touch Hungary.

The Article 26 infringement sits within a broader EU-level legal battle over whether the Energy Charter Treaty's arbitration clause is compatible with EU law for intra-EU disputes. Two landmark Court of Justice rulings — Achmea (2018) and Komstroy (2021) — held that intra-EU investor-state arbitration under bilateral investment treaties and the ECT respectively is incompatible with EU law. The EU as a whole withdrew from the Energy Charter Treaty in April 2024, but the ECT's 20-year sunset clause means Article 26 claims filed before withdrawal can still proceed for existing investments.

MOL, Hungary's national oil and gas company, filed an ECT Article 26 claim against an unspecified EU member state; the Commission's infringement opinion signals that Brussels considers Hungary's tolerance of or participation in the MOL arbitration as a treaty violation. The case illustrates the ongoing tension between national energy companies using ECT arbitration and the EU's post-Achmea, post-Komstroy legal framework.