Tesla Inc.'s handling of Chief Executive Elon Musk's proposal to take the carmaker private and its failure to promptly file a formal disclosure has raised governance concerns and sparked questions about how companies use social media.

Musk stunned investors Aug. 7 by announcing on Twitter that he was considering taking Tesla private in a potential $72 billion transaction and that "funding" had been "secured."

Tesla's shares closed up 11 percent before retrenching after The Wall Street Journal reported that the U.S. Securities and Exchange Commission (SEC) had asked Tesla why Musk announced his plans on Twitter and whether his statement was truthful.