Fourth television network
The early history of television in the United States, particularly between 1956 and 1986, was dominated by the Big 3 television networks: NBC, CBS, and ABC. Fourth television network was used within the industry during this era to refer to a theoretical fourth commercial broadcast (over-the-air) television network that would operate as a direct competitor to the "Big Three". Prior to 1956, the DuMont Television Network operated as an existing fourth network alongside ABC, CBS, and NBC, but an inability to find solid financial ground, a weaker affiliate base, and internal competition from co-owner Paramount Pictures all contributed to DuMont's closure.
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