The Fox Broadcasting Company, commonly known simply as Fox and stylized in all caps as FOX, is an American commercial broadcast television network owned by Fox Corporation and headquartered in New York City, with master control operations and additional offices at the Fox Network Center in Los Angeles and the Fox Media Center in Tempe. Launched as a competitor to the Big Three television networks (ABC, CBS, and NBC) on October 9, 1986, Fox went on to become the most successful attempt at a fourth television network. It was the highest-rated free-to-air network in the 18–49 demographic from 2004 to 2012 and again in 2020, and was the most-watched American television network in total viewership during the 2007–08 season. Fox and its affiliated companies operate many entertainment channels in international markets, but these do not necessarily air the same programming as the U.S. network. Most viewers in Canada have access to at least one U.S.-based Fox affiliate, either over the air or through a pay television provider, although Fox's National Football League broadcasts and most of its prime time programming are subject to simultaneous substitution regulations for pay television providers imposed by the Canadian Radio-television and Telecommunications Commission (CRTC) to protect rights held by domestically based networks. Fox is named after the film studio that was originally called 20th Century Fox, and (indirectly) after the producer William Fox, who had founded one of the film studio's predecessors, Fox Film, before it was merged with another company in 1935. After it was purchased by Rupert Murdoch's Australian conglomerate News Corporation, the hyphen between "Century" and "Fox" was removed. (In 2013, its corporate sibling was split off as a stand-alone entertainment conglomerate, known as 21st Century Fox, which was acquired in 2019 by The Walt Disney Company.) Fox is a member of the North American Broadcasters Association and the National Association of Broadcasters. History Origins 20th Century Fox (now 20th Century Studios) had been involved in television production as early as the 1950s, producing several syndicated programs. Following the demise of the DuMont Television Network in August 1956, after it became mired in severe financial problems, the NTA Film Network was launched as a new "fourth network". 20th Century Fox would also produce original content for the NTA network. The film network effort would fail after a few years, but 20th Century Fox continued to dabble in television through its production arm,