(Bloomberg) -- Soros Fund Management’s US equity positions tumbled by almost $2 billion in the first quarter to $5.2 billion, fueled by a decline in the value of its stake in electric-vehicle maker Rivian Automotive Inc. and exits from large holdings including IHS Markit Ltd.

George Soros’s investment firm reported its biggest single position was Rivian, which went public in November. Its 19.84 million shares were worth about $1 billion at the end of March, according to a filing Friday. The stock has plunged 47% since the end of the first quarter, extending its decline for the year to 74%. 

The billionaire philanthropist’s investment firm is overseen by Dawn Fitzpatrick and managed about $25 billion at the start of 2022, including in public and private equity and through hedge funds. The filing discloses US equity holdings, but it doesn’t give a complete picture of Soros’s positions, including hedges. 

Soros, 91, uses his vast fortune to fund groups promoting justice, democracy, human rights and progressive politics through his Open Society Foundations. He has poured billions into his philanthropic efforts, and most of his firm’s assets now belong to the foundations rather than to the Soros family. He personally is worth $8.5 billion, according to the Bloomberg Billionaires Index.

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