“It’s a very clever way for him to cash in some of his holding, while offloading the decision to his fans,” he said. “But selling is a perfectly logical thing to do when you own stocks that are clearly overvalued.

“In order for Tesla’s valuation to make sense, you would have to assume it had a monopoly in the production and software development of electric cars,” he said.

Mr Musk has repeatedly said that he believed Tesla’s share price was too high. In September, the founder said he was already planning to sell some of his stake, as his marginal tax rate would exceed 50pc when his stock options expired.

Other members of Tesla’s board, including Mr Musk’s brother Kimbal Musk, sold millions of dollars worth of shares in the company in November. 

‘Tesla will continue to grow’

Nevertheless, it remains one of the most popular stocks among DIY investors. The car-maker is also a favourite at the fund house Baillie Gifford, and is one of the top holdings in Britain’s largest investment trust, Scottish Mortgage. In its latest annual report, Scottish Mortgage’s co-manager Tom Slater wrote he was confident about Tesla’s potential.

He said: “The head start it has on competitors leads us to believe that it could enjoy a period of comparative advantage. If it can realise the potential of its [artificial intelligence] capabilities and make its fleet largely autonomous, then this advantage will be greater still.”

Large investors are confident the stock will continue to climb. Analysts at the broker Jefferies upgraded their share price target to $1,400, pointing to Tesla’s improved profit margins and a gradual move towards a broader customer base. 

Phillippe Houchois, of the broker, said that while the “normalisation” of Tesla cars was years away, its scale in the electric car sector was hard to beat. He said that the company looked “more scaled up” than its competitors, thanks to the integration of all elements across its business model, from production to software design.