The Daily Beast published details on "Hemisphere," a secret program run by AT&T to provide law enforcement agencies with location data gleaned from trillions of call records.
The searches are performed by AT&T without legal warrants but with administrative subpoena, according to the report, as a product for the law enforcement agencies.
The Daily Beast article also says alleges that the Hemisphere has grown to become a very lucrative operation for AT&T.
http://www.thedailybeast.com/articles/2016/10/25/at-t-is-spying-on-americans-for-profit.html