Breakup of the Bell System in the context of Southwestern Bell Corporation

Local exchange carrier (LEC) is a regulatory term in telecommunications for the local telephone company.

In the United States, wireline telephone companies are divided into two large categories: long-distance (interexchange carrier, or IXCs) and local (local exchange carrier, or LECs). This structure is a result of 1984 divestiture of then-regulated monopoly carrier American Telephone & Telegraph. Local telephone companies at the time of the divestiture are also known as Incumbent Local Exchange Carriers (ILEC).

Western Electric Co., Inc. was an American electrical engineering and manufacturing company that operated from 1869 to 1996. A subsidiary of the AT&T Corporation for most of its lifespan, Western Electric was the primary manufacturer, supplier, and purchasing agent for all telephone equipment for the Bell System from 1881 until 1984, when the Bell System was dismantled.

For much of the 20th century, Western Electric's equipment, especially their telephones, was ubiquitous throughout most of the United States and Canada. This was a result of the Bell System's near-total monopoly on phone service, combined with the legal ban on connecting third-party premises equipment to the telephone network.

Verizon Communications Inc. (/vəˈraɪzən/ və-RY-zən), is an American telecommunications company headquartered in New York City. It is the world's second-largest telecommunications company by revenue and its mobile network is the largest wireless carrier in the United States, with 146.1 million subscribers as of June 30, 2025.

The company was formed in 1983 as Bell Atlantic as a result of the breakup of the Bell System into seven companies, each a Regional Bell Operating Company (RBOC), commonly referred to as "Baby Bells." The company was originally headquartered in Philadelphia and operated in the states of Pennsylvania, New Jersey, Delaware, Maryland, Virginia, and West Virginia.

The Bell System was a system of telecommunication companies, led by the Bell Telephone Company and later by AT&T, that dominated the telephone services industry in North America for over 100 years from its creation in 1877 until its antitrust breakup in 1983. The system of companies was often colloquially called Ma Bell (as in "Mother Bell"), as it held a vertical monopoly over telecommunication products and services in most areas of the United States and Canada. At the time of the breakup of the Bell System in the early 1980s, it had assets of $150 billion (equivalent to $450 billion in 2024) and employed over one million people.

Beginning in the 1910s, American antitrust regulators had been observing and accusing the Bell System of abusing its monopoly power, and had brought legal action multiple times over the decades. In 1974 the Antitrust Division of the U.S. Department of Justice brought a lawsuit against Bell claiming violations of the Sherman Act. In 1982, anticipating that it could not win, AT&T agreed to a Justice Department-mandated consent decree that settled the lawsuit and ordered it to break itself up into seven "Regional Bell Operating Companies" (known as "The Baby Bells"). This ended the existence of the conglomerate in 1984.

The Bell Labs Technical Journal was the in-house scientific journal for scientists of Bell Labs, published yearly by the IEEE society.

The journal was originally established as The Bell System Technical Journal (BSTJ) in New York by the American Telephone and Telegraph Company (AT&T) in 1922. It was published under this name until 1983, when the breakup of the Bell System placed various parts of the companies in the system into independent corporate entities. The journal was devoted to the scientific fields and engineering disciplines practiced in the Bell System for improvements in the wide field of electrical communication. After the restructuring of Bell Labs in 1984, the journal was renamed to AT&T Bell Laboratories Technical Journal. In 1985, it was published as the AT&T Technical Journal until 1996, when it was renamed to Bell Labs Technical Journal. The journal was discontinued in 2020. The last managing editor was Charles Bahr.