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.

Rocio Concha, director of policy and advocacy at Which?, said Mastercard & Ors v Walter Hugh Merricks is a ‘hugely important win for consumers’.

‘From today, the route to collective redress will be fairer, simpler and more attainable, and many cases that are currently on hold will be able to proceed to trial.’

Meanwhile, City firm Covington & Burlington said the judgment marks ‘a clear lowering of the bar from the standard set by the CAT’ and affirms that 'it is not the job of the CAT to set up too many hurdles’.

However Freshfields Bruckhaus Deringer, acting for Mastercard, emphasised the ‘very unusual circumstances’ in which the judgment was handed down.

Mark Sansom, joint head of global antitrust litigation group, said: ‘It is important to note that there was a 2-2 split between the judges on a number of the key issues, with two of the judges accepting that the CAT had been entitled to reject the proposed claim rather than certify it to proceed. The tribunal will now engage with the implications of that at a future hearing.’

The judgment was due to be a 3:2 majority decision in favour of dismissing the appeal. However, the sudden death of Lord Kerr – who presided at the hearing in May – left a 2-2 split. The two justices who opposed the dismissal of the appeal did not dissent, saying it would be unjust and ‘hugely wasteful of resources’ to re-hear the case.

In a statement, Merricks said: ‘The Supreme Court’s decision means that claims relating to losses affected by anti-competitive business wrongdoing in other sectors can be pursued. Today’s judgment sends a powerful signal to companies that infringe competition law that they do so at their financial peril.’