Berkshire Hathaway recently filed its second-quarter 13F form, revealing its stock holdings at the end of June.

Buffett began buying shares in the consumer electronics giant in 2016 and continued buying, turning Apple into Berkshire Hathaway's biggest individual stock holding in 2017. Apple represented roughly 50% of Berkshire Hathaway's investment portfolio at its peak in 2023.

Shares of some of UnitedHealth’s peers got a bump in the wake of Berkshire’s investment in the healthcare giant, and they all look cheaper based on price relative to expected earnings.