Tesla CEO Elon Musk is being investigated in connection with his $44 billion acquisition of Twitter, the microblogging site said in a court filing on Thursday. The lawyers on behalf of social media company wrote in a court filing in Delaware that Musk is presently under investigation by federal authorities for his conduct in connection with the acquisition of Twitter, Bloomberg reported.

“Elon Musk is presently under investigation by federal authorities for his conduct in connection with the acquisition of Twitter,” attorneys for Potter Anderson Corroon LLP wrote in a filing dated October 6 and unsealed Thursday.

Lawyers representing Twitter said the company had requested Musk’s attorneys for months to produce their communications with federal authorities but they failed to do so, citing ‘investigative privilege’. The lawyers wrote that the company has asked the court for access to documents that Musk has given to authorities. “This game of ‘hide the ball’ must end,” the company said in the court filing. Twitter’s lawyers said the documents ‘bear upon key issues in this litigation.’