The company may be under criminal investigation for alleged irregularities in its Medicare business—but it's been touched by the Warren Buffett effect.

Warren Buffett's Berkshire Hathaway has acquired 5 million shares in UnitedHealth Group , a regulatory filing showed on Thursday, sending the health insurer's stock up 7% in extended trading.

UnitedHealth (UNH) stock climbed 6.7% in Thursday afternoon trading after Warren Buffett's Berkshire Hathaway (BRK.B) (BRK.A) disclosed that it acquired a new stake in the health insurer during Q2 2025.

Warren Buffett’s Berkshire Hathaway (BRK.B) updated its portfolio for the second quarter of 2025, surprising investors with a new stake in UnitedHealth Group (UNH) while reducing its large holding in Apple (AAPL).

Buffett & Co. picked up UnitedHealth stock on the cheap, with the embattled blue chip one of the newest holdings in the Berkshire Hathaway equity portfolio.

Berkshire Hathaway just disclosed that it dumped $1.6 billion into a sinking ship, and Wall Street instantly paid attention.

Berkshire Hathaway’s portfolio added six new stocks, including the three new secret stocks. Warren Buffett was a net seller of stocks for the eleventh straight quarter.

The conglomerate sold Apple shares during the second quarter, though the iPhone maker remains Berkshire’s largest stockholding.

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