A Tribunal Court judge has blocked a £14 billion class action lawsuit against Mastercard for overcharging customers, agreeing that the claims were not suitable under the current collective actions regime.
The decision will be of significant relief to Mastercard given that it was set to be the largest and most complex case in UK legal history, involving 45 million people in Britain over a period of 16 years.
The case would also have tested the parameters of the relatively new Consumer Rights Act which only introduced US-style collective class actions in 2015 for breaches of UK or EU competition law.
In a statement Mastercard said: "We welcome the Competition Appeal Tribunal's judgment refusing certification for the proposed collective action."
The class action was brought by a US law firm, Quinn Emanuel Urquhart & Sullivan, back in 2007 following MasterCard's unsuccessful appeal against a European Commission ruling that its fees were anti-competitive.
More specifically, the case focused on the use of interchange fees charged by numerous credit and debt card companies - fees which the card companies say are charged to merchant banks to cover the cost of innovation, security and operational overheads.
This latest ruling from the Competition Appeal Tribunal follows a High Court ruling back in January in a dispute with retailers that Mastercard's use of interchange fees had been lawful and not anti-competitive.
The class action case may not be over for Mastercard though. The London-based lawyer and named representative for the class action, Walter Merricks, said he was "surprised" and "disappointed" by the ruling and said he was considering an appeal.
Mr Merricks, a former leader of the Financial Ombudsman Service said: "I am concerned that this new regime, designed to benefit consumers, may never get off the ground. The granting of the collective proceedings order in this case would have allowed 46m consumers to recover the losses caused to them by Mastercard’s proven illegal conduct.
"It is, however, unfortunate that the Tribunal considered that it was not satisfied that my experts would be able to get the evidence to show that the illegal fees charged by Mastercard to businesses were then passed on to consumers in the form of higher prices."
Of particular frustration to Mr Merrick was the Tribunal's determination over the inability to accurately calculate the loss suffered by all 46m consumers included in the suit and the result that "consumers should get nothing at all".
"I believe these are matters my advisers could have addressed and overcome had the claim been allowed to proceed. I am actively considering with my advisors and litigation funders the possibility of an appeal," he said.