Facebook Antitrust Probe by State Attorneys General Announced

New York State Attorney General Letitia James announced on Friday she’s leading a multi-state investigation into whether Facebook is engaging in behavior that has unfairly disadvantaged its users and stifled competition.

James is being joined in the investigation by attorneys general from Colorado, Florida, Iowa, Nebraska, North Carolina, Ohio, Tennessee, and the District of Columbia.

“Even the largest social media platform in the world must follow the law and respect consumers. I am proud to be leading a bipartisan coalition of attorneys general in investigating whether Facebook has stifled competition and put users at risk,” James says in a statement. “We will use every investigative tool at our disposal to determine whether Facebook’s actions may have endangered consumer data, reduced the quality of consumers’ choices, or increased the price of advertising.”

The investigation is in addition to a separate antitrust probe by the Federal Trade Commission that Facebook disclosed in July. The existence of that federal antitrust investigation was confirmed on the same day the company was hit with a $5 billion fine by the Federal Trade Commission for violating an earlier pledge to not misuse consumer data.

A Facebook spokesperson did not immediately respond to a request for comment from Fortune. However, CEO Mark Zuckerberg and fellow executives have previously denied claims that the company has an unfair advantage and should be broken up, despite calls from some Democrats, including presidential candidate Elizabeth Warren, to split the company apart. Facebook executives have also said that each of Facebook’s services has outside competition.

Facebook shares were down 2.2% Friday morning after James’ announcement. However the company’s stock has a history of resilience, despite its troubles. The day that the $5 billion fine for privacy violations—the biggest in FTC history— was announced, shares of Facebook surged.