Oral arguments in the appeal MasterCard v Commission came before the European Court of Justice this July. At stake is the multilateral interchange fee (MIF), which costs European retailers an estimated €12 billion a year. MasterCard's main claim was that following its flotation on the stock market in 2006, it ceased to be ‘an association of undertakings' and so, its decision on MIF levels should not be subject to cartel law. EuroCommerce spoke in support of the European Commission, insisting on the huge and unjustified costs borne by merchants and their customers. A final decision is not expected before 2012.