Shares of Tesla fell 7 per cent on Friday after David Einhorn's hedge fund Greenlight Capital slammed the electric car-maker, adding to losses sparked by CEO Elon Musk mocking the US Securities and Exchange Commission (SEC) on Twitter.

Mr Musk stirred nerves about a settlement of his securities fraud lawsuit by calling the SEC the “Shortseller Enrichment Commission” on Twitter, just hours after a federal judge ordered him and the regulator to justify their settlement.

“Just want to say that the Shortseller Enrichment Commission is doing incredible work,” Mr Musk, a frequent critic of investors betting against the electric car company, said in the tweet on Thursday. “And the name change is so on point!”

In its quarterly letter, Greenlight said its short position on Tesla was its second biggest winner in the third quarter. The hedge fund said Mr Musk has been deceptive, and the car-maker's woes resemble those of Lehman Brothers before its collapse. – Reuters