AT&T vs Telefonica

AT&T Inc. is an American multinational telecommunications corporation, headquartered at Whitacre Tower in downtown Dallas, Texas. AT&T Inc. began its existence as Southwestern Bell Corporation, one of seven Regional Bell Operating Companies created in 1983 in the divestiture of the American Telephone and Telegraph Company following the 1982 United States v. AT&T antitrust lawsuit. Southwestern Bell changed its name to SBC Communications Inc. in 1995. In 2005, SBC purchased former parent AT&T Corp. and took on its branding, with the merged entity naming itself AT&T Inc. and using the iconic AT&T Corp. logo and stock-trading symbol.

Telefnica, S.A. is a Spanish broadband and telecommunications provider with operations in Europe, Asia, North America and South America. Operating globally, it is one of the largest telephone operators and mobile network providers in the world. The company started as a public telecommunications company. Its head office is in the Distrito Telefnica in Madrid. As well as the Telefnica brand, it also trades as O2, Vivo and Movistar.