After pressure from the top Democrat on the Senate Finance Committee, four top telecommunications companies pledged to end contracts with a firm that gathered data on users’ locations and sold it without their consent.

The Federal Communications Commission in May launched an investigation into Securus Technologies, a company that provides telephone services for prisons, after learning the firm was giving the federal government location information purchased from major wireless carriers. Sen. Ron Wyden of Oregon, who initially pressured the agency to launch the review, asked Federal Communications Commission Chairman Ajit Pai to recuse himself from it due to a prior involvement with Securus.