Burry’s Scion Asset Management owned bearish put contracts against 235,500 shares of the ARK Innovation ETF (ticker ARKK) at the end of the second quarter, according to a regulatory filing Monday. The new position was valued at almost $31 million, the filing says.

The flagship exchange-traded fund of Cathie Wood and her firm Ark Investment Management lured billions in the past year after her thematic tech-focused bets trounced the market in 2020. But Wood and Ark have struggled to maintain momentum amid concerns about lofty prices and accelerating inflation.

Burry has been warning about unsustainable valuations in the market for months. In June, he cautioned that retail investors could be getting drawn into “the mother of all crashes” by investing in cryptocurrencies and meme stocks.

A put contract gives Scion the right to sell shares in the ETF before a certain date and at a previously agreed price. Its value increases if shares drop below the threshold. The exact terms of the puts, and when they were purchased, are undisclosed.

Burry has been indirectly betting against Wood for some time via a big position against Tesla Inc.—one of Ark’s top picks and ARKK’s biggest holding.

Monday’s filing, a quarterly requirement of hedge funds above a certain size, also shows that Burry increased his bearish wagers against the electric-vehicle maker, with puts on 1,075,500 Tesla shares. That’s up from 800,100 shares in the first quarter.

ARKK dropped 2.6% as of 12:25 p.m. in New York amid broad tech-stock declines. Tesla slumped 4.7% as the U.S. opened a formal investigation into the company’s Autopilot system.

Burry rose to widespread fame when his successful bets against mortgage securities during the financial crisis were featured in “The Big Short,” the movie version of Michael Lewis’s best-selling book. Christian Bale portrayed the Scion founder and chief executive officer.

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