Almost every UK adult could soon be owed £300 from Mastercard if a £14 billion damages claim goes ahead.
Former financial ombudsman Walter Merricks is attempting to bring legal action against the company on behalf of around 46 million people.
He claims millions of customers paid higher prices in shops because of allegedly excessive transaction fees charged by Mastercard.
If the claim wins, almost every adult in the UK could be owed £300 from the card giant, even if you have never owned a credit card.
Mr Merricks' proposed class action was thrown out in July 2017 but senior judges ruled yesterday (April 16) that the Competition Appeal Tribunal (CAT) had applied the wrong legal test in deciding whether to give the claim the go-ahead.
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His proposed claim will go back to the CAT, which will have to reconsider whether to allow it to proceed.
In a statement after the ruling, Mr Merricks said: "I am very pleased with today's decision.
"It is nearly 12 years since Mastercard was clearly told that they had broken the law by imposing excessive card transaction charges, damaging consumers over a prolonged period.
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"As a result we all had to pay higher prices in the shops than we should have done - while Mastercard have pocketed the profits.
"It's now time for Mastercard to admit the damage they did, to apologise to the British public, and to agree to pay the compensation they owe."
What Mastercard said
Mastercard said it will fight the case, saying: “This decision is not a final ruling and the proposed claim is not approved to move forward, rather the court has simply said a re-hearing on certain issues should happen."
The proposed action is an "opt-out" claim, which means potential claimants - anyone who was over the age of 16 and resident in the UK for at least three months between 1992 and 2008, and who made a purchase from a business that accepted Mastercard - are part of the action unless they specifically choose not to be.
This means that if the claim wins, you could get around £300.
