https://arstechnica.com/tech-policy/2018/06/verizon-and-att-will-stop-selling-your-phones-location-to-data-brokers/

Verizon and AT&T have promised to stop selling their mobile customers' location information to third-party data brokers, following a security problem that leaked the real-time location of US cell phone users.

Sen. Ron Wyden (D-Ore.) recently urged all four major carriers to stop the practice, and today he published responses he received from Verizon, AT&T, T-Mobile USA, and Sprint.