The National Retail Federation and the Retail Industry Leaders Association has asked the U.S. Supreme Court to let stand an appeals court ruling striking down a 2012 settlement of a class action lawsuit over Visa and Mastercard swipe fees. The settlement was brought by a small group of retailers and trade associations claiming to represent the retail industry.

The judge approved the settlement even though the NRF and others said it failed to reform the alleged price-fixing system under which Visa and MasterCard set fees for credit cards. Rather than lower the fees, the card companies proposed in the settlement that the fees be passed along to consumers as a surcharge. Major retailers rejected the proposal. The NRF asked an appeals court to overturn the settlement, claiming a broad cross section of the retail industry opposed the deal. The appeals court ruled in NRF’s favor saying that merchants were inadequately represented. That ruling, however, has been appealed to the Supreme Court.

If the ruling does not stand, current and future merchants will be barred from ever suing Visa or MasterCard over swipe fees in the future, per the settlement. And swipe fees may be shifted to the consumer.