Facebook shares tumbled on Monday after it was reported that federal authorities had divvied up how best to approach regulatory concerns about major tech companies, potentially opening the door for an official antitrust investigation in Mark Zuckerberg’s social media giant.

According to The Wall Street Journal, the Federal Trade Commission (FTC) will take charge of any antitrust investigation into Facebook. The FTC will also be responsible for overseeing Amazon. The Justice Department, meanwhile, will handle investigations related to Alphabet, Google’s parent company of Google. The departments share authority when it comes to antitrust law, hence the divvying out of responsibilities.

The FTC has been a persistent thorn in Facebook’s side since the Cambridge Analytica scandal last year, when it was revealed that the personal information of tens of millions of Americans had been shared without consent with a data analytics firm that had a sordid backstory and connections to the Trump campaign.

In response, the FTC launched an investigation to find out whether Facebook had violated an agreement the two bodies had previously made regarding consumer privacy. In April, it was reported the commission would fine Facebook up to $5 billion for privacy violations, though the fine has not yet been settled.

The number represents a drop in the bucket for a company with Facebook’s operating profits, but it would still be the largest privacy-related civil penalty ever handed out by the FTC.

Coupled with the most recent developments, it’s becoming clear that lawmakers want to see more oversight of Big Tech companies. 2020 candidates like Sen. Elizabeth Warren (D-MA) are also urging the government to step in — Warren’s campaign recently put up a giant billboard in San Francisco calling for the breakup of Big Tech — and even Republicans like Sen. Ted Cruz (R-TX) have backed the idea. South Bend, Indiana, Mayor Pete Buttigieg, also a 2020 candidate, has compared tech companies to monopolies.

This attention is not likely to yield any time soon, especially as political misinformation gains steam online, in advance of the election. Despite Zuckerberg’s prior assurances that Facebook is ready to thwart any potential election meddling, evidence points to the fact that 2020 may simply be a repeat of 2016.

Last month, an altered video of House Speaker Nancy Pelosi (D-CA), slowed down to make her appear drunk, went viral on Facebook. Despite repeated criticisms, the social media giant refused to take the video down, arguing that it was a form of “self-expression.” The Daily Beast later tracked down the alleged creator of the video, who was allegedly involved in managing two large political Facebook groups, for which he received advertiser revenue, though the man has denied responsibility for the viral clip.

The developments on the FTC’s new regulation agreement should be treated as welcome news from those seeking stronger oversight of Big Tech, especially bearing in mind that Congress has previously showed an inability, or an unwillingness, to fully grasp how central technology companies make their profits. In an infamous exchange during a congressional hearing last August, for instance, then-Sen. Orrin Hatch (R-UT) asked Zuckerberg how his company could possibly sustain its business model if users were not forced to pay for the service.

“Senator, we run ads,” Zuckerberg responded.