Kluwer Arbitration Blog: Should issue estoppel apply to questions of state immunity?
30 April 2025
In a new article for the Kluwer Arbitration Blog, Simon Bushell, Liang-Ying Tan and Deekshitha Swarna of Seladore Legal analyse a recent landmark Court of Appeal judgment which confirmed that issue estoppel arising from a foreign judgment can apply to determinations of state immunity under the State Immunity Act 1978.
This judgment forms part of the ongoing international litigation surrounding enforcement of arbitral awards exceeding US$50 billion in favour of the former majority shareholders of Yukos Oil Company. The Court’s decision reinforces the approach that English courts will apply established common law doctrines, such as issue estoppel, rather than treating state immunity as an overriding principle of public policy.
The authors explore the wider implications for investor-state arbitration and cross-border enforcement strategy, emphasising the importance of jurisdictional considerations and strategic planning in complex multi-jurisdictional disputes.