International Arbitration: English Court Rules that ICSID & ECT Awards Cannot be Assigned

In a judgment handed down on Monday 10 November 2025, the English Commercial Court (the Court) ruled that arbitration awards made pursuant to the International Centre for Settlement of Investment Disputes (ICSID) Convention or under the Energy Charter Treaty (ECT) are not capable of assignment.

This decision is significant, as it may preclude a purported assignee of an ICSID or ECT award (for example, a related group entity following a corporate reorganisation, or a third-party purchaser) from directly enforcing that award in England & Wales.

A brief case note follows. The full judgment can be read here: Operafund Eco-Invest SICAV Plc v The Kingdom of Spain [2025] EWHC 2874 (Comm).

The Facts

Between July 2008 and July 2009, Operafund Eco-Invest SICAV Plc and Schwab Holding AG (the Claimants) invested in a number of solar energy plants in Spain, allegedly in reliance upon representations made on behalf of Spain as to the minimum tariffs and incentives which would be extended to renewable energy projects. Spain is alleged to have breached the provisions of the ECT by subsequently passing legislation revoking those tariffs and incentives.

The Claimants commenced arbitration against Spain on 31 July 2015 under the ICSID Convention, pursuant to Article 26 of the ECT. An award was rendered on 6 September 2019, awarding the Claimants damages of EUR 29.3 million (the Award). On 9 August 2021, the Claimants applied for an order registering the Award in England & Wales, which was granted on 14 September 2021 (the Order). The Order gave the Award the same force and effect for the purposes of execution as a judgment of the High Court.

On 6 January 2023, Spain applied to set aside the Order on grounds of state immunity. Final determination has been adjourned pending decision by the UK Supreme Court of a similar issue in Infrastructure Services Luxembourg S.à r.l. v The Kingdom of Spain [2024] EWCA Civ 1257 (listed for hearing from 1 to 4 December 2025).

On 31 January 2024, the Claimants purported to assign all rights, interests, and benefits under or in respect of the Award to Blasket Renewable Investments LLC (Blasket), and applied to substitute Blasket as claimant in the proceedings pursuant to CPR 19.2(4)(a). Spain opposed this application, on the basis that the Award was not assignable as a matter of international law.

The Decision

The Court held as follows:

• There is no rule of customary international law providing that arbitration awards made under the ICSID Convention either are or are not assignable.
• However, construing the ICSID Convention as a whole, arbitration awards made under the ICSID Convention are not capable of assignment.
• As a matter of construction of the ECT itself, even if the Court were wrong and other arbitration awards made under the ICSID Convention were assignable, awards concerning claims under the ECT would not be assignable.
• Any rights accruing to the Claimants pursuant to the Order were consequently not assignable.

The judgment may be appealed to the Court of Appeal, and subsequently to the UK Supreme Court.

Our international disputes team is on hand to assist with any queries following this decision.