A Mastercard spokesman told The Telegraph that the huge class action lawsuit revived by the UK Court of Appeal “is completely unsuitable to be brought under the collective actions regime.”

The UK Supreme Court announced last week that it will hear the company’s challenge to the £14 billion ($17.1 billion) class action. In 2017, the Competition Appeal Tribunal dismissed the case, saying it did not meet the standards required by the country’s new class action system. Earlier this year, though, the UK Court of Appeal revived it.

U.S. Chamber Institute for Legal Reform President Lisa A. Rickard said in an earlier op-ed that the case represents the “heart of the Consumer Rights Act,” which established class action litigation in the UK, and warns of an impending “litigation monster” if the appellate court decision is upheld.