The result, government contended, was to slow the development of innovations such as smart cards.
In 2001, a federal judge in New York ordered the two associations to drop their exclusionary rules, a ruling that was upheld by the U.S. Court of Appeals for the 2nd Circuit in fall 2003.
Both Visa and MasterCard expressed disappointment at the Supreme Court's refusal to hear their appeal.
"We continue to believe our rule is pro-competitive. That's why we defended it all the way up to the Supreme Court," said Daniel Tarman, senior vice president at Visa USA.
Tarman added that Visa officials believe that their competitors' problems resulted from their own products, not from Visa and MasterCard rules.
"Every consumer who wants an American Express card clearly knows how to get one. No court decision is going to fix that," Tarman said.
"We do not envision any fundamental changes in the marketplace," he added.
Further, Tarman said, banks will be reluctant to go into deals with American Express because "American Express competes with banks, [while] Visa is a bank-owned and bank-governed association."
Officials of MBNA, a big Delaware-based card issuer, said the company plans to issue its first American Express cards within the next several weeks, and marketing materials will be going out to millions of potential customers by the end of the year. These cards will be credit cards, many of them "affinity" cards that allow the cardholder to support a favorite institution or association, but some will be "rewards" cards that offer benefits to consumers who use them.
Some industry experts agreed that the decision will affect the credit card business, but they said it will be less than the winners are forecasting.
David Robertson, publisher of the Nilson Report, a California-based industry publication, said American Express will gain market share over the next few years, but added: "I don't think anyone should think this is going to revolutionize the credit card business because there's no way it could."