New York Attorney General Letitia James has said 46 other state attorney generals have joined her antitrust investigation into Facebook.
The investigation, announced in September, focuses on whether Facebook's dominant market position has stifled competition, put consumer data at risk, limited consumer choices, and resulted in advertisers paying more money.
"We will use every investigative tool at our disposal to determine whether Facebook's actions stifled competition and put users at risk," James said in a statement on Tuesday.
The antitrust investigation commenced last month, and initially only had support from the attorney generals of eight states -- New York, Florida, Colorado, Iowa, Nebraska, North Carolina, Ohio, and Tennessee -- along with Washington DC.
Since then, the amount of participating attorney generals has grown to 47, with the attorney generals of Arizona, Arkansas, Connecticut, Delaware, Idaho, Illinois, Indiana, Kansas, Kentucky, Louisiana, Maine, Massachusetts, Michigan, Minnesota, Mississippi, Missouri, Montana, Nevada, New Hampshire, New Jersey, New Mexico, North Dakota, Oklahoma, Pennsylvania, Rhode Island, South Carolina, Texas, Vermont, Virginia, Wisconsin, Wyoming, and the territory of Guam now a part of the state-level investigation.
A number of other states have also joined, James said, but they currently cannot confirm their participation in pending investigations.
"Big tech must account for its actions. I am proud to join my Republican and Democrat colleagues in efforts to ensure tech giants can no longer hide behind complexity and complicity," Louisiana Attorney General Jeff Landry said.
"We need to protect competition in markets so that consumer benefit from choices, so that their privacy is protected, and to ensure that the next generation of tech innovators aren't snuffed out by their powerful competitors," North Carolina Attorney General Josh Stein added.
Facebook and other big tech companies are already the subject of various federal antitrust investigations. In June, the House Judiciary Committee launched an antitrust investigation of Facebook, Google, and other tech companies. The US Department of Justice (DOJ) in July also launched a sweeping antitrust review into the industry's competitive conditions. The Federal Trade Commission (FTC) and the DOJ are also both reportedly investigating Facebook over antitrust concerns.
At state level, other big tech companies are also facing similar heat from regulators. Google is currently the focus of a similar antitrust investigation commenced by Texas Attorney General Ken Paxton. That investigation, which looks into whether Google is engaging in monopolistic behavior with its online search and advertising business, has so far garnered support from attorneys general from 48 states, Puerto Rico, and Washington DC.
Facebook has already been at the back-end of regulatory restitution, having been recently fined $5 billion by the FTC for privacy violations. As part of the settlement, Facebook also agreed to conduct a massive overhaul of its consumer privacy practices and remove CEO Mark Zuckerberg as its sole privacy decision-maker.
Meanwhile, Facebook shares were up in after-hours trading as the company exceeded Q2 revenue expectations.
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