A correction to what I said - they are not common carrier for mobile data. They are common carriers for mobile voice communications.
There is a whole series of FTC v AT&T lawsuits which outline this argument and the extent to which they are subject to FTC regulation, if you're interested.
There is a whole series of FTC v AT&T lawsuits which outline this argument and the extent to which they are subject to FTC regulation, if you're interested.