The ARK Innovation ETF got out of Nvidia before its eye-popping rally.

It took a bear-market plunge in NVIDIA Corp.'s stock for famed investor Cathie Wood to once again take a stake in the artificial-intelligence leader within her top fund.

Wood has been a big believer in AI, characterizing it as the most disruptive technology in history. And she had invested in Nvidia before it became a household name.

But within her flagship ARK Innovation exchange-traded fund ARKK, Wood unloaded her Nvidia position too soon, and that fund missed out on Nvidia's big AI-fueled rally that ignited in the middle of 2023 and extended through 2024. Through last week, only a few of Wood's smaller ETFs owned Nvidia's stock.

On Monday, Wood's largest fund, the $6.03 billion ARK Innovation ETF, bought 151,979 shares of Nvidia, which were valued at $14.8 million at Monday's closing price.

The stock bounced 3.5% on Monday and climbed another 2.1% as of midday trading on Tuesday.

ARK didn't immediately respond to a MarketWatch request for comment on the purchase.

The Innovation ETF's holding sheet shows the shares bought on Monday are the only ones it owns as of Tuesday. That makes Nvidia the ETF's 32nd-largest holding, with a 0.33% weighting. To put that in perspective, Tesla Motors Inc.'s stock is the ETF's largest holding, with its $535.8 million stake carrying an 11.94% weighting.

The purchases came after Nvidia's stock had dropped 14.6% in two days, in the wake of the Trump administration's tariff announcement, to close Friday at an 11-month low. At that price, the stock has tumbled 37% since closing at a record $149.43 on Jan. 6.

Wood characterizes a disruptive technology as something that leads to steep declines in costs while dramatically improving performance. On that basis, she has said the AI "revolution" is moving at a rate that is four to six times faster than the semiconductor space.

"Every sector in the global economy is harnessing AI, and the number of businesses spinning up on this disruptive platform is likely to be unprecedented," wrote Brett Winton, chief futurist for ARK Venture Investment, in a recent research note to clients.

On Nvidia specifically, Wood last year defended her decision to sell by citing the big opportunities in software. "We believe that for every dollar of AI hardware sold, another $10 of AI software will be sold," she said on a Wall Street Journal podcast in February 2024. "Everyone now understands that Nvidia is the key chip player. It's created the AI age in a sense, but we do think that it has become a check-the-box stock."

A month later, she said in an ARK shareholder letter that "without an explosion in software spending," she wouldn't be surprised to see a spending pause around AI hardware.

Among Wood's other ETFs, the $1.7 billion ARK Next Generation Internet ETF owned 130,495 Nvidia shares, the $1 billion ARK Fintech Innovation ETF held 87,330 shares and the $915.3 million ARK Autonomous Technology & Robotics ETF ARKQ had a stake of 122,611 shares.