Regional Bell Operating Company

The Regional Bell Operating Companies (RBOC) are the result of United States v. AT&T, the U.S. Department of Justice antitrust suit against the former American Telephone & Telegraph Company (later known as AT&T Corp.). On January 8, 1982, AT&T Corp. settled the suit and agreed to divest its local exchange service operating companies. Effective January 1, 1984, AT&T Corp.'s local operations were split into seven independent Regional Bell Operating Companies known as "Baby Bells". RBOCs were originally known as Regional Holding Companies (RHCs). Currently, three companies have the RBOCs as predecessors. They are AT&T Inc., Verizon, and CenturyLink. Some other companies are holding on smaller segments of the companies.

After the Modification of Final Judgment, the resulting Baby Bells were originally:

Prior to 1984, AT&T Corp. also held investments in two smaller and otherwise independent companies, Cincinnati Bell and Southern New England Telephone (SNET). Following the 1984 breakup, these became fully independent as well. All nine local-exchange holding companies were assigned a share of the rights to the Bell trademark.

After divestiture, AT&T Corp. was prohibited from using the Bell name or logo (with the notable exception of AT&T's Bell Laboratories) and those trademarks which would be shared by the RBOCs and the two companies AT&T partially owned. Since the BellSouth acquisition, Cincinnati Bell has been the only former AT&T associated company still carrying the "Bell" name.

Additionally, Bell Canada, the former Bell Telephone Company of Canada (founded in 1880) and which started separating from the Bell System in 1956, and completely by 1975, continues to use the "Bell" trademarks, which it owns outright in Canada.

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