This case-note examines the Kingdom of Spain v. Infrastructure Services Luxembourg S.À.R.L. and another and Republic of Zimbabwe v. Border Timbers Ltd and another UK Supreme Court (UKSC) decision. (UK Supreme Court, The Kingdom of Spain v. Infrastructure Services Luxembourg S.À.R.L. and another; Republic of Zimbabwe v. Border Timbers Ltd and another [2026] UKSC 9, judgment of 4 March 2026, https://supremecourt.uk/uploads/ uksc_2024_0155_0156_judgment_bf1a2df59f.pdf (accessed on 2 Sep 2026)) Its central submission is that the decision is significant not chiefly because it restates the orthodox proposition that immunity from execution remains preserved by Article 55 of the ICSID Convention, but because it resolves the threshold question whether a debtor state may invoke adjudicative immunity in order to prevent registration of an ICSID award altogether. (Ibid., paras. 19–21, 86, 144) The UKSC held that – by virtue of Article 54(1) ICSID Convention – the appellant states had submitted to the jurisdiction within the meaning of section 2(2) of the State Immunity Act 1978 (SIA). (Ibid., para 144) Article 55 ICSID Convention, by contrast, preserves immunity only from execution. (Ibid., paras. 86, 88) That distinction follows not only from the general structure of the Convention, but also from the nature of the obligation created by Article 54(1): the ICSID Convention requires the award to be treated as binding and its pecuniary obligations to be enforced as if it were a final judgment, whereas execution is left by Article 54(3) ICSID Convention to the law concerning the execution of judgments in the forum state, and immunity from execution is preserved by Article 55 ICSID Convention. The judgment does not remove sovereign immunity from the ICSID post-award framework. However, it identifies more precisely where the immunity objection remains available and where it does not.
European Investment Law and Arbitration Review