MasterCard is facing a £19 billion lawsuit - claimed to be the biggest in UK legal history - over allegations that it imposed "illegal" card fees that were ultimately borne by UK consumers.
The claim, brought under the Consumer Rights Act of 2015 which paved the way for class action lawsuits, is being led by former financial ombudsman Walter Merricks.
The suits comes after MasterCard lost a 10-year legal battle with the European Commission over the level of interchange fees levied on debit and credit card charges.
A statement by litigators Quinn Emanuel, says: "MasterCard lost this battle at every level and showed complete disregard for its cardholders and consumers at large, focusing instead on generating unlawful profits."
The firm, which has raised £40 million to take the case to court, says that all UK consumers, including cash purchasers - not just MasterCard holders - have lost money as a result.
Says Merricks: “The prices of everything we all bought from 1992 to 2008 were higher than they should have been as a result of the unlawful conduct of MasterCard. My aim is to get the redress to which UK consumers are entitled and to ensure that MasterCard cannot hold on to the illegal profits it made. This case should send a signal to companies that break competition laws at the expense of UK consumers that they do so at their financial peril.”
MasterCard has refuted the claims and says it will fight the challenge in the courts. “We firmly disagree with the basis of this legal claim," a spokesman says. "Electronic payments deliver real value to people online, instore and everywhere. MasterCard is committed to providing ever more convenient, safe and secure payments to all our customers, including consumers, retailers, governments and banks.”
In June last year, MasterCard shelled out $61 million to UK supermarket chain Tesco in the first of an expected wave of settlements by card schemes over interchange fee lawsuits lodged by British retailers. Tesco was one of 20 UK retailers which filed suit against MasterCard in 2013 alleging historic overpayment of 'anti-competitive' interchange fees.