In the wake of Supreme Court judgments in 2017–18 pronouncing the contours of the subject, restricting claims for indirect transfers, incidental benefits and compound interest, a theme of recent English and Welsh cases on unjust enrichment is the limits of the reach of the claim. Therefore a claim in unjust enrichment: cannot subvert a judgment or court order without that judgment being set aside (Gibbs v Lakeside Developments § 6); cannot lie for benefits paid under a contract unless it is set aside in accordance with contractual principles (Elston v King § 5); and cannot lie for recovery of overpaid local taxes where there is an applicable statutory scheme (Lone v Hounslow London Borough Council § 9). Test Claimants in the Franked Investment Income Group Litigation v HMRC [2016] EWCA Civ 1180; [2017] STC 696; [2018] RLR § 211 was argued in the Supreme Court in February 2020. In the meantime, there is evidence of continuing reluctance to embrace the supposed retrospectivity of mistakes of law where to do so would undermine a valid compromise (Elston v King). The potential role of economic duress has provoked judicial disagreement and that, too, looks likely to receive consideration in the Supreme Court (Times Travel v Pakistan International Airlines § 12).

1. Alfred Street Properties Ltd (formerly known as Killultagh Estates Ltd) v National Asset Management Agency [2020] EWHC 397 (Comm) (Comm Ct: Phillips LJ).

Extendable interest rate swaps—payments made when swaps subject of disputed extension—restitution—defence of good consideration—change of position