TELECOMMUNICATIONS

AT&T; Sues 3 Biggest Rivals: Stepping up efforts to win back its valuable long-distance franchise, American Telephone & Telegraph has sued MCI Communications, Sprint and WilTel. The move aims to force AT&T;’s rivals to comply with a federal court ruling issued last November requiring all long-distance telephone companies to file with the Federal Communications Commission details of contracts they have with their business customers. The disclosure requirement took effect about three weeks ago and resulted from a lawsuit filed by AT&T;, which has been required to make identical disclosures since 1934. Officials of the three firms shrugged off the suit as an attempt by AT&T; to intimidate them.