The Federal Communications Commission plans to fine four mobile phone carriers a total of $200 million for making consumers’ real-time location data available to third parties, Reuters reported Thursday. The companies will be able to challenge the amount of the fines, expected to be announced Friday, before they become final, Reuters reported.

The FCC did not immediately respond to a request for comment on the report.

Motherboard reported last year that AT&T, Sprint, Verizon, and T-Mobile were selling users’ real-time location data to third-party distributors. In the wake of that report, the carriers pledged to stop selling the data or, in some cases, said they had already cut ties with the offending contractors.

“comically inadequate fines”

Still, some carriers have defended the sharing of the data as a general practice, even as they condemned specific partners. In a letter published this May, AT&T described data-sharing as “an important feature commonly used by app developers to provide location services.”

“For example, ride-sharing apps use A-GPS to make sure the car shows up in the right location,” the letter read. “For these reasons, reports of purported improper use of A-GPS are incorrect.”

The FCC launched an investigation into location data practices shortly after the Motherboard report, and lawmakers have pushed the commission to demonstrate progress at various points during the ensuing year. FCC chairman Ajit Pai said last month that “one or more wireless carriers apparently violated federal law.”

Reached for comment, Sen. Ron Wyden (D-OR) criticized the FCC’s slow action in response to the privacy violations. “This issue only came to light after my office and dedicated journalists discovered how wireless companies shared Americans’ locations willy nilly,” Wyden said in a statement. “[Pai] only investigated after public pressure mounted. And now his response is a set of comically inadequate fines that won’t stop phone companies from abusing Americans’ privacy the next time they can make a quick buck.”

In January, FCC Commissioner Jessica Rosenworcel also criticized the agency for taking so long to act on the reports. “It’s chilling to consider what a black market could do with this data,” she said. “It puts the safety and privacy of every American with a wireless phone at risk.”