The United States Travel Agent Registry (USTAR) is “a not-for-profit business cooperative of travel agents throughout the United States” that “represents the interests of U.S. travel agents in [matters concerning] automation, technology, sales and marketing, and distribution.” USTAR filed complaints against Delta Air Lines, Inc., United Air Lines, Inc., American Airlines, Inc., and Continental Airlines, Inc., in Dockets OST-98-4776,4785,4786, and 4836, respectively.