Citadel, a prominent hedge fund, has significantly reduced its holdings in NVIDIA stock. According to regulatory filings, Citadel sold approximately 500,000 shares of NVIDIA in the second quarter of 2024, reducing its holdings from $60 million at the end of March to $19 million at the end of June. This move is part of a broader trend where several billionaire investors, including Ken Griffin of Citadel, are selling off substantial portions of their NVIDIA holdings, potentially signaling concerns about the tech sector's short-term prospects and the company's future growth.