Bell Operating Companies

The Bell System was the system of companies, led by the Bell Telephone Company and later by AT&T, which provided telephone services to much of the United States and Canada from 1877 to 1984, at various times as a monopoly. On December 31, 1983, the system was broken up into independent companies by a U.S. Justice Department mandate.

The colloquial term Ma Bell (as in "Mother Bell") was often used by the general public in the United States to refer to any aspect of this conglomerate, as it held a near-complete monopoly over telephone service in most areas of the country, and is still used by many to refer to any telephone company. Ma Bell is also used to refer to the various female voices behind recordings for the Bell System: Mary Moore, Jane Barbe, and Pat Fleet (the current voice of AT&T).

In 1877, the American Bell Telephone Company, named after Alexander Graham Bell, opened the first telephone exchange in New Haven, Connecticut. Within a few years local exchange companies were established in every major city in the United States. Use of the Bell System name initially referred to those early telephone franchises and eventually comprised all telephone companies owned by American Telephone & Telegraph, referred to internally as associated companies, regional holding companies, or later Bell operating companies (BOCs).

In 1899, American Telephone & Telegraph (AT&T) acquired the assets of its parent, the American Bell Telephone Company. Originally American Bell had created AT&T to provide long-distance calls between New York and Chicago and beyond. AT&T became the parent of American Bell, and thus the head of the Bell System, because regulatory and tax rules were leaner in New York than in Boston, where American Bell was headquartered. Later, the Bell System and its moniker "Ma Bell" became a term that referred generally to all AT&T companies of which there were four major divisions:

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