Facebook. Photo: Allmy/Shutterstock.com

Thirty-one states Tuesday, including Delaware, officially signed onto the New York-led antitrust investigation into social media giant Facebook, joining dozens of others investigating whether the tech giant has hurt competition and limited consumer choice.

The move is the latest to put the regulatory spot on global technology companies' business practices, with efforts focusing on conglomerates such as Facebook and Google.

The investigation into Facebook's practices stems for a leadership team consisting of attorneys general from New York, Colorado, Florida, Iowa, Nebraska, North Carolina, Ohio, Tennessee and the District of Columbia.

New York Attorney General Letitia James said 47 states have signed on to the investigation, with 39 doing so openly, while eight "cannot confirm their participating in pending investigations." James did not elaborate.

In addition to Delaware, those newly joining the investigation include attorneys general from Connecticut, Illinois, New Jersey, Pennsylvania  and Texas. They say their focus is on potential antitrust violations.

"Social media is a critical part of doing business in today's economy," Connecticut Attorney General William Tong said in a statement Tuesday. "Any effort by Facebook to unlawfully stifle competition could cause wide-ranging harm to smaller companies, restrict consumer choice, and increase costs for all."

"With Facebook's dominance comes an obligation to ensure they're not stifling competition," Pennsylvania Attorney General Josh Shapiro tweeted Tuesday. "We'll follow the evidence and take any action necessary to protect consumers."

Delaware Attorney General Kathy Jennings added: "I am dedicated to protecting the rights of Delawarean consumers, which includes the right to participate in the Internet economy without fear of being taken advantage of by social media companies and other service providers."

And James said the initial investigation found Facebook "may have put consumer data at risk, reduced the quality of consumers' choices, and increased the price of advertising."

No one from Facebook's press office responded to a request for comment by press time.

The attorneys general investigation adds to mounting scrutiny. The Washington Post reported that James and others were also investigating Google's parent company, Alphabet Inc. And Reuters reported the U.S. Justice Department would be opening an antitrust investigation of Facebook.

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