mastercardAs many as 46 million people across Britain could possibly benefit from a lawsuit brought against credit card processing giant MasterCard that demands £14 billion or $19 billion worth of damages. The suit alleges that excessive fees were charged shows court documents that were filed in a London court.

The case was filed by a former ombudsman who alleges the payments company had charged high fees that were unlawful to stores when their shoppers paid with a credit or debit card and those were then passed on to the consumer through higher prices.

MasterCard allegedly did this for over 16 years from 1992 to 2008, said the lawsuit that was over 600 pages long.

This was what the lawsuit called an invisible tax, said Walter Merricks, who filed the lawsuit.

MasterCard, said Merricks, behaved in a disgraceful fashion in this and did not accept what they were doing was hurting the UK consumer.

In a prepared statement released by MasterCard, the payments company has denied wrongdoing and continues to disagree firmly with the claim. It intends to oppose it in a vigorous manner.

The lawsuit was filed after the antitrust regular of the European Union found the fees of MasterCard in 2014 to owners of stores to process payments that were international with the EU, to be excessive.

One law firm in the UK said the damages were the largest damages to ever be filed in Britain.

The suit is being filed under a law that means consumers are automatically claimants unless they want to opt out.

Anyone living in Britain that has used a credit or debit card, cash or checks and was 16 years or older during the period that the suit covers by the lawsuit, would be automatically a claimant.

Merricks was the head of financial services ombudsmen in Britain for 10 years through 2009, helping settle disputes between financial services companies and consumers.

Banks have paid over £24 billion in compensation for misspelling insurance for loan payments, making it the costliest scandal in Britain in the financial services sector.

Consumers that do not live any longer in Britain, but lived there anytime from 1992 to 2008, can become part of the class action suit against MasterCard.

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