An online advertising clearinghouse relied on by Google, Yahoo and Facebook is using controversial cookies that come back from the dead to track the web surfing of Verizon customers.
The company, called Turn, is taking advantage of a hidden undeletable number that Verizon uses to monitor customers’ habits on their smartphones and tablets. Turn uses the Verizon number to re-spawn tracking cookies that users have deleted.
“We are trying to use the most persistent identifier that we can in order to do what we do,” Max Ochoa, Turn’s chief privacy officer, told ProPublica.
Turn’s zombie cookie comes amid a controversy about a new form of tracking the telecom industry has deployed to shadow mobile phone users. Last year, Verizon and AT&T users noticed their carriers were inserting a tracking number into all the Web traffic that transmits from a users’ phone 2013 even if the user has tried to opt out.
Users complained that the tracking number could be used by any website they visited from their phone to build a dossier about their behavior 2013 what sites they went to, what apps they used.
In November, AT&T stopped using the number. But Verizon did not, instead assuring users on its website that “it is unlikely that sites and ad entities will attempt to build customer profiles” using its identifiers.
When asked about Turn’s use of the Verizon number to re-spawn tracking cookies, a Verizon spokeswoman said, “We’re reviewing the information you shared and will evaluate and take appropriate measures to address.”