• Billionaire investor Stanley Druckenmiller told Bloomberg on Wednesday that selling all his Nvidia stock this year was a "big mistake."
• Nvidia was Druckenmiller's top holding a year ago, but he sold it after the stock tripled in 2023.
• The shares are up another 174% this year, and Druckenmiller has missed much of the continuing rally.

Billionaire investor Stanley Druckenmiller said on Wednesday that his decision to sell out of Nvidia this year was a "big mistake."

"I've made so many mistakes in my investment career — one of them was I sold all my Nvidia probably somewhere between $800 and $950," Druckenmiller said in an interview on Bloomberg. "I own none and I owned none the last 400 points."

Druckenmiller's comments do not reflect Nvidia's 10-for-1 stock split, which went into effect in June. The stock closed Wednesday at $135.72. On a split-adjusted basis, his sales would have taken place at between $80 and $95.

Nvidia has been the primary beneficiary of the artificial intelligence boom, selling its graphics processing units, or GPUs, to top cloud companies and the biggest developers of large language models. The stock soared 239% last year and is up another 174% in 2024, closing at a fresh record on Monday.

Earlier this year, Druckenmiller revealed on CNBC's "Squawk Box" that he cut his Duquesne Family Office's position in Nvidia in late March, saying "we've had a hell of a run."

Taking the split into account, Duquesne owned about 6.18 million shares at the start of the year, 1.76 million at the end of the first quarter and 214,000 when the second quarter closed. In the third quarter of last year, Nvidia was his top holding. At the time, he owned 8.75 million shares worth around $400 million.

If he held onto that entire stake, it would currently be worth about $1.19 billion. Duquesne has not released its third-quarter holdings yet.

"It tripled in a year, and I thought the valuation was rich," Druckenmiller told Bloomberg. "Nvidia is a wonderful company and were the price to come down, we'd get involved again. But right now, I'm licking my wounds from a bad sale."

Nvidia is expected to release quarterly results in November, but most of its top customers, including Meta, Microsoft, Amazon and Alphabet, will report financials later this month.

Druckenmiller told CNBC in May that Nvidia was "a little overhyped now, but underhyped long term." He added that he was introduced to Nvidia in 2022, when "I didn't even know how to spell it."

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