But the incident led the SEC to launch an investigation into the matter, and Bloomberg's sources say the DOJ probe will operate alongside the SEC's inquiry. The SEC is said to be looking into the legality of how Musk announced the plan to go private and whether he properly notified the company's investors of how statements like that would be made ahead of time. Bloomberg says that federal prosecutors initiated a fraud investigation following the CEO's tweets.
Update 9/18/18 1:10PM ET: A Tesla spokesperson sent us the following statement:
"Last month, following Elon's announcement that he was considering taking the company private, Tesla received a voluntary request for documents from the DOJ and has been cooperative in responding to it. We have not received a subpoena, a request for testimony or any other formal process. We respect the DOJ's desire to get information about this and believe that the matter should be quickly resolved as they review the information they have received."