Industry experts claim that Discover Financial Services may gain USD 4 billion in a lawsuit against Visa and MasterCard. The lawsuit regards restrictions imposed on banks by the latter two card issuers in order to prevent competition, thus violating the federal antitrust law.

In 2001, a judge's decision prevented Visa and MasterCard from forcing banks to choose between cards issued by the two companies and the ones from Discover and American Express, but this was withdrawn in 2004. Discover reports that in Q3 2008, its net income dropped 11 percent to USD 180 million, without taking into consideration the disposal of its UK credit-card business. Visa and MasterCard representatives claim that Discover's business model is the main reason the company is at a disadvantage, since it has not been involved in any significant agreement with banks since 2004 and financial institutions earn less from smaller rivals than from major networks. 

Statistics indicate that in 2007, Visa owned almost half of the US credit and debit card market, while MasterCard 28 percent, as compared with Discover which had a share of 3.8 percent. US credit card purchases reached USD 2.17 trillion in value in 2007, over USD 426 billion in 1993.