By Jemma Slingo2020-12-11T15:42:00+00:00 The Supreme Court’s ruling against Mastercard will make it easier for group damages claims to proceed to trial, commentators have said. However, the card issuer’s solicitors have stressed the ‘very unusual circumstances’ of the judgment, in which justices were divided on key issues. In a widely awaited judgment, the Supreme Court today dismissed Mastercard’s appeal, finding that a 2017 Competition Appeal Tribunal (CAT) judgment was undermined by errors of law. The case has now been remitted to the tribunal for reconsideration. In 2017 the CAT refused to certify the case, which is brought by former financial services ombudsman Walter Merricks CBE on behalf of 46 million credit and debit card holders. It is the first major opt-out action brought under the Consumer Rights Act 2015 and is believed to be the largest damages claim ever brought in the UK, at an estimated £14bn.