As the world’s largest telecommunications company, AT&T is active across a dizzying array of markets, products, and services. For much of the 20th century, the company ran a monopoly on telephones in the US market and remains one of the most profitable companies in the world with total 2020 revenues of $171 billion.

AT&T’s origins stretch back to the founding of the Bell Telephone Company by Alexander Graham Bell in 1877, two years after his invention of the first telephone. In 1880, the company began the construction of a long-distance wire system across the US, and in 1885, Bell and his father-in-law founded the ‘American Telephone and Telegraph Company’, which immediately acquired Bell. A series of friendly agreements with the American government in the 1910s and 20s saw AT&T take control of virtually all regional phone networks, in addition to its control of the long-distance network. This was eventually broken up after growing suspicion of monopoly abuse in the 1970s, resulting in the 1984 spin-off of the regional phone providers into new companies.

In response to this considerable loss of revenue, AT&T launched an ultimately unsuccessful foray into the computer market, before expanding profitably into the broadband and wireless spaces. The 2000s saw AT&T re-purchasing many of the divisions spun off in 1984 while maintaining strong investment in new growth technologies. Wireless telecommunications provides the bulk of current revenue, alongside profitable segments in broadband, physical equipment, and video communication services. In 2018, AT&T acquired WarnerMedia, better known as the film producers Time Warner, contributing to an ongoing diversification of AT&T’s business portfolio.

As the eleventh largest American company by revenue, AT&T is a popular holding among institutional investors. Vanguard, Blackrock, and State Street are all major shareholders. Geographically, AT&T is focused on the US and Latin American markets.