TheStreet. Warren Buffett is arguably the most successful investor of all time. He's amassed an amazingly massive net worth by buying and usually holding stocks for the long haul. Trained under legendary value fund investor Benjamin Graham,

UnitedHealth has been the Dow’s worst performer of 2025, but jumped 13% Friday. Here’s why Buffett and other leading hedge funds suddenly love the stock.

Berkshire Hathaway's latest regulatory filing revealed that the company took a considerable stake in UnitedHealth. The 5 million-share, $1.6 billion stake makes the massive health insurer the 18th-biggest position in Berkshire's portfolio. Buffett's company also trimmed its positions in Apple and Bank of America.