For all of 2015, AT&T had $15.9 billion in free cash flow, which TBR defines as operating cash flow minus capital expenditures. Verizon had $21.2 billion, and Sprint had a loss of $3.2 billion. TBR estimated that T-Mobile had $100 million, since it has not reported yet.
"There is a clear duopoly by AT&T and Verizon, as both continue to get strong," Antlitz said. "T-Mobile is fighting hard and staking a position as a value play while Sprint has just fizzled away."
Antlitz said a company's cash flow is the most visible way to judge a balance sheet, since accounting practices make it easier to hide problems in other areas. "Cash flow is important since either you have the cash or don't and there's no tinkering with it," he said.
Comparing AT&T and Verizon on IoT
As both AT&T and Verizon focus on IoT, there's so far not much differentiation.
"These two companies are very similar and usually neck and neck in whatever they do," Antlitz said. "You rarely see a margin between them. Verizon is talking more about IoT, but if you look at the underlying story, AT&T is a little ahead."
While Verizon is producing IoT innovations, it also has been secretive about its plans, Antlitz said. "AT&T is not only talking, but showing business results for IoT."
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