The High Court has partially allowed Jazztel’s claim in unjust enrichment for restitution of unlawful SDRT payments paid under mistake of law. Claims for restitution of payments made prior to 8 September 2003 are exempt from FA 2004 s 320(1), which purported retrospectively to dis-apply s 32(1)(c) of the Limitation Act 1980. Section 32(1) provided that limitations periods for mistake claims only start to run when the claimant ‘has discovered the … mistake … or could with reasonable diligence have discovered it’. However, the court held that s 320(1) is effective to disapply s 32(1)(c) and curtail mistake claims brought after 8 September 2003.