[bimmer44]

I'm intrigued by this type of case - this article doesn't mention any specific legislative requirement that fees should have been less during the period concerned. It's a strange precedent that a company can be retrospectively liable for charging "too much".

This is similar to the case of Apple and their tax dues in Ireland.

Maybe someone with a better grasp of legal matters can explain a mechanism that gives this case a chance. Otherwise I can't see this claim succeeding without causing a great deal of business uncertainty.

[rayiner]

It's not that unusual in the antitrust context. The whole theory of antitrust is that anti-competitive behavior allows a company to charge prices greater than they would be able to charge in a competitive market. If a company is found to have engaged in anticompetitive conduct, it's common in a civil suit for the measure of damages to be the difference between the prices actually charged and some judicially-determined market price (usually based on an econometric expert analysis).

[bimmer44]

This makes sense - I think the Reuters article was quite misleading. I posted another comment [1] with a link to a Guardian article that supports what you wrote.

[1] https://news.ycombinator.com/item?id=12463745

[FLUX-YOU]

My guess is they are trying to get it labeled as an invisible tax because a mastercard transaction fee wouldn't have shown on the receipt or the customer wouldn't have known they are paying higher prices due to the transaction fee.