'The industry is looking for alternatives to the duopoly': Here are the potential winners and losers if AT&T buys AppNexus (T, FB, GOOG)

AT&T is in talks to buy digital ad firm AppNexus, Cheddar reported.
That likely signals that the company's plans to challenge advertising titans Google and Facebook.
There's sure to be winners and losers if a deal goes through.
Just a week after AT&T won a landmark ruling allowing its merger with Time Warner to continue without conditions, it appears its acquisition plans aren't slowing down anytime soon.
The company is in talks to buy digital ad firm AppNexus, C