US federal regulators and more than 45 state prosecutors have sued Facebook, accusing the social media company of taking illegal actions to buy up rivals and stifle competition.
The lawsuit is one of the most significant legal actions the US government has taken against the firm.
Officials are asking the court to consider breaking up the company, which also owns Instagram and WhatsApp.
Facebook has previously defended its actions.
Officials said the lawsuits were focused on Facebook’s 2012 acquisition of Instagram, 2014 purchase of WhatsApp and rules governing outside software developers.
“No company should have this much unchecked power over our personal interaction and social interactions,” New York Attorney General Letitia James said. “That’s why we are taking action today.”