Over a year and a half ago, each of the four major US carriers was in some way involved with an incident that revealed how carriers were selling location data of its subscribers to whoever wanted to pay for them. It involved a couple of "middle men" companies who could eventually sell location data to whoever wanted to buy it. It eventually involved Securus, a prison company that used carrier information to track phones without owners' permission. On Friday, FCC Chairman Ajit Pai sent a letter to key members of Congress, declaring that the FCC has conducted its investigation and concluded...