Divestiture - technical definition

The breakup of AT&T. By federal court order, AT&T divested itself on January 1, 1984 of its 23 operating companies, which became known as the Regional Bell Operating Companies (RBOCs). Bell Labs was renamed AT&T Bell Labs, and its Western Electric manufacturing division became AT&T Technologies. The demarcation point of the physical split was the Class 4 switching center. Except for those that handled large metropolitan regions, all Class 4 offices went to AT&T, and all Class 5 offices went to the RBOCs. It was the switching office class hierarchy within the Bell system that made Divestiture possible, because there were clear borders between long distance and local service. See Class 4 switch, Bellcore and Trivestiture.