https://www.theverge.com/2018/6/19/17478934/verizon-selling-real-time-location-data-third-party-securus-wyden

Verizon has pledged to stop selling data that can pinpoint the location of its mobile users to third-party intermediaries, according to The Associated Press. Verizon is the first carrier to end the controversial practice after Sen. Ron Wyden (D-OR) revealed that one of the companies that purchased the real-time location-tracking data from carriers wasn’t verifying if its users had legal permission to track cellphone users through its service.

In a letter to carriers and the FCC, Sen. Wyden said that Securus Technologies — a company that mainly monitors phone calls to inmates in jails and prisons across the country and also sells real-time location data to law enforcement agencies who must upload legal documents such as a warrant stating they have the right to access the data — wasn’t actually verifying if those documents were legitimate. Securus did not “conduct any review of surveillance requests,” Wyden wrote in his letter to the FCC.