"Am considering taking Tesla private at $420".
On Twitter Tuesday, Musk said he has secured funding from a private buyer.
Tesla also made the news just before this tweet, when the Financial Times reported that Saudi Arabia's Public Investment Fund had amassed a previously unreported stake of "between 3 and 5 percent" of Tesla's shares.
"Funding secured", the tweet added, offering no further details on where the funds would come from or when.More news: Luxury yacht in graft probe arrives in Malaysian port
Tesla has been publicly traded since 2010, and has seen its share price rise from just under $20 then to $360 at time of writing.
Tesla did not immediately respond to a request for comment.
The tweet suggested Mr Musk was looking at a plan to buy outstanding shares in the firm for $420 each, around a fifth higher than the share's current price.
It's never a boring day when Elon Musk takes to Twitter.
The tweets have added to speculation about Tesla, which is spending heavily as it ramps up production of its latest vehicle, the Model 3.