Report: Top antitrust official leaving DOJ

Both Varney and Pozen struck an aggressive stance at the nation's top antitrust regulator, culminating in the lawsuit that eventually forced AT&T to abandon its takeover and pay T-Mobile $4 billion in cash and spectrum.

The collapse of the deal was a stunning development after AT&T's concerted lobbying effort. It also served warning to industry that the administration would not look fondly upon deals that could reduce competition in fast-growing sectors like wireless technology.