Supreme Court hands down judgment on opt-in versus opt-out in collective proceedings

19/12/25

On 18 December 2025 the Supreme Court (Lord Sales, Lord Leggatt and Lady Rose (with whom Lord Burrows and Lord Richards agreed)) handed down judgment in Evans (Respondent) v Barclays Bank Plc & Ors (Appellants) [2025] UKSC 48. This is the first judgment of the Supreme Court on whether collective proceedings under section 47B Competition Act 1998 should be certified on an opt-in or opt-out basis.

The Respondent, Mr Evans, applied to act as class representative in respect of proposed collective proceedings on an opt-out basis. The claims sought to be combined were follow-on claims seeking damages for losses caused by infringements of competition law in FX spot trading found by the European Commission in two Decisions dated 16 May 2019.

The majority of the Competition Appeal Tribunal decided that the proposed collective proceedings should not be brought on an opt-out basis, relying on two factors identified in the legislative regime as relevant to a decision whether to allow opt-out proceedings: the strength of the claims, and whether it was practicable for them to be brought as opt-in proceedings. The Court of Appeal set aside the Tribunal’s decision on the opt-in/opt-out issue and held that proceedings could proceed on an opt-out basis. The Supreme Court unanimously allowed the appeal of the Appellant banks.

As to the strength of the claims, the Supreme Court held that the weakness of the claims as assessed by the Tribunal was properly regarded by the Tribunal as a factor weighing strongly against opt-out proceedings. If the claim is very weak it is likely to be more difficult to justify resort to the opt-out procedure as striking a fair procedural balance between the claims and the defendants. It is also likely to be difficult to justify resort to the opt-out procedure as a proportionate way of providing access to the Tribunal for the vindication of such a claim.

As to practicability, the Supreme Court considered that, if it is practicable for the proceedings to be brought as opt-in proceedings, then generally speaking they should be. The Tribunal has a wide case-management power of evaluation and discretion in making its decision. The assessment of practicability made by the majority of the Tribunal was within the ambit of the evaluative judgment legitimately open to the Tribunal to make.

The Supreme Court further held that the Court of Appeal had been wrong to treat a subsequent decision of the Commission concerned with a different infringement as admissible in English proceedings, against defendants who were not addressees of that decision, as evidence of facts found. The Supreme Court confirmed that the rule in Hollington v Hewthorn applies to the Tribunal.

The judgment is available here.