AT&T Stops Using Undeletable Phone Tracking IDs; Verizon Continues

Julia Angwin, ProPublica:

AT&T says it has stopped its controversial practice of adding a hidden, undeletable tracking number to its mobile customers’ Internet activity.

Why would AT&T do this?

The tracking numbers can be used by sites to build a dossier about a person’s behavior on mobile devices – including which apps they use, what sites they visit and for how long.

Ah, to sell user data to advertisers.

Edmonds said AT&T may still launch a program to sell data collected by its tracking number, but that if and when it does, “customers will be able to opt out of the ad program and not have the numeric code inserted on their device.”

If AT&T is more interested in its customers than its advertisers — that’s a big if — wouldn’t it be better for AT&T to make the sale of your mobile activity data opt in, instead of opt out? And what about Verizon?

A Verizon spokeswoman says its tracking program is still continuing, but added “as with any program, we’re constantly evaluating.”

Verizon uses the tracking number to identify the users’ behavior and offer advertisers insights about users gleaned from that data. Verizon says the data it sells is not tied to a users’ identity.

Verizon does not seem to give a hoot about its customers. Something to think about: identifying a user with a single data point is difficult, but as you add more data points uncovering the identity of a user becomes easier. I’m relieved that I am not an AT&T or a Verizon customer.