Nico Leslie and Daniel Carall-Green represented Dassault Aviation SA in a successful challenge before the High Court of the jurisdiction of the tribunal in an arbitration requested against it by Mitsui Sumitomo Insurance Co Ltd. Cockerill J handed down judgment in December 2022 and the case has since been shortlisted for the ‘Most Important Decision’ award at this year’s Global Arbitration Review Awards.

The decision is significant in that it provides clarification in relation to an often-misunderstood area of the law of assignment and for its treatment of the interaction of different legal systems in the context of arbitration agreements. Specifically, Cockerill J confirmed that where a transfer took place under a Japanese insurance statute in apparent breach of an English-law contractual prohibition on transfer, the focus is not (as has at times been suggested) on the mechanism of the transfer (i.e., whether it is “by operation of law”), but rather whether there is a sufficient “degree” or “taint” of voluntariness in the transfer. Cockerill J ruled that the transfer was prohibited.  The judge’s decision is the first authority directly addressing this issue for almost a century.

The winners will be announced at the awards ceremony at the InterContinental Paris Le Grand on the 30 March, as part of Paris Arbitration Week.