Tesla Inc (NASDAQ:TSLA) shares are being shorted by Scion Asset Management LLC, a private investment firm founded by Michael J. Burry, who was the subject of a book “The Big Short” and subsequent 2015 film of the same name where he was played by Christian Bale.

Scion announced it had put options on 800,100 shares in the electric car maker at the end of the first quarter, which were worth US$534mln, Reuters reported, citing a regulatory filing with the US SEC.

Burry is known for betting more than a billion dollars against the US housing bubble, reportedly making a profit of about US$2.7bn, which was the subject of the book and the film.

Burry has been sceptical of Tesla’s sky-high valuations, having tweeted in February, “my last Big Short got bigger and Bigger and BIGGER,” referring to Tesla’s surge in market capitalisation.

“Enjoy it while it lasts,” he said.

Shares in the electric car maker rose to a record US$883 in January, but have since fallen on concerns about being overvalued.

The shares closed at $576.83 on Monday, valuing the company at about US$555bn, still more than most of the next half dozen car manufacturers put together and larger than the GDP of Argentina, and after initially opening lower on Tuesday quickly rose 2% to above $587.