Tesla’s founder Elon Musk wiped $14bn off the carmaker’s value after tweeting that its share price was too high.
It also knocked $3bn off Mr Musk’s own stake in Tesla as investors promptly bailed out of the company.
“Tesla stock price too high imo,” he said, one of several tweets that included a vow to sell his possessions.
In other tweets, he said his girlfriend was mad at him, while another simply read: “Rage, rage against the dying of the light of consciousness.”
In 2018, a tweet about Tesla’s future on the New York stock market led to regulators fining him $20m and Mr Musk agreeing to have all further posts on the platform pre-screened by lawyers.
On Friday, the Wall Street Journal reported it had asked the billionaire if he was joking about the share price tweet and whether it had been vetted, receiving the reply “No”.
Tesla’s share price has surged this year, putting the electric carmaker’s value at close to $100bn, a mark that would trigger a bonus payment of hundreds of millions of dollars to the entrepreneur.