T-Mobile is not on the same network as AT&T. There are three major cellular networks in the country. AT&T and T-Mobile are two of these three networks; Verizon is third.
The merger between AT&T and T-Mobile USA mobile operators was blocked by the Department of Justice on Wednesday saying that keeping these giant companies separate would keep competition in the wireless industry and help save American workers' jobs.
Thus, to save American workers' jobs, FTC blocked the 2011 merger between at&t and t-mobile.
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