`` Billionaire Elon Musk is putting his money where his mouth is. `` `` He purchased about $1 billion worth of Tesla stock, his first open market purchase of the electric vehicle-maker's shares since February 2020, regulatory filings show. `` `` Musk bought 2.57 million shares on Sept. 12, paying between $372.37 and $396.54 per share, according to a regulatory filing on Sept. 15. The purchase is Musk's largest insider stock purchase ever by value and widely seen as a vote of confidence in the company by its ...