Sprint is studying regulatory concerns and could launch a bid in the first half of next year, the people said. A deal could be worth more than $20 billion, depending on the size of any stake in T-Mobile that Sprint tries to buy. A merger of the third- and fourth-largest U.S. carriers would create a sizable competitor to industry leaders Verizon Wireless and AT&T Inc. But it would likely face tough opposition from antitrust authorities, who worry consumers could suffer without a fourth national competitor to keep a check on prices.
Sprint has yet to decide whether it is going to go ahead with a bid, which could be risky due to concern from regulators. AT&T tried to purchase T-Mobile in 2011 for $39 billion; however, the Justice Department blocked the deal saying it would "substantially lessen competition" in the wireless market.
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