Regional Bell Operating Company

The Regional Bell Operating Company (RBOC for short) was a corporate business. They were created from the antitrust lawsuit from the United States Department of Justice against the American Telephone and Telegraph group (or AT&T) in 1974. This lawsuit was settled under the Modification of Final Judgment on January 8, 1982.

The AT&T Corporation agreed getting rid of their local exchange service networks. That became effective January 1, 1984. Those local operating service companies were broken into seven independent Regional Bell Operating Companies, also known as the Baby Bells.

The RBOCs were known as also the Regional Holding Companies (RHCs in shorthand). Three companies (as of December 2024) have RBOCs for their earlier companies. They include AT&T (formerly Southwestern Bell and the BellSouth), Verizon (previously Bell Atlantic and GTE), and Lumen Technologies (formerly the CenturyTel and CenturyLink).

The Baby Bells

When the Bell System was phased out, the following geographic area RBOCs/Baby Bell networks were named as follows. They were:

• Ameritech
• Bell Atlantic
• BellSouth
• NYNEX
• The Pacific Telesis
• Southwestern Bell Corporation (or SBC Communications)
• US West

The mergers

Southwestern Bell Corporation (or SBC) and AT&T (along with BellSouth) were combined to become "new" AT&T in 2005 or 2006. Likewise, US West on June 30, 2000 was merged to Qwest (which later merged into CenturyLink eleven years later and Lumen Technologies in 2020).

The other related networks

Other related communications to the former RBOCs include Consolidated Communications (also called FairPoint) and Frontier Communications.