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.

Warren Buffett’s Berkshire Hathaway revealed a position in embattled healthcare giant UnitedHealth Group while showing smaller stakes in longtime holdings Apple and Bank of America, according to a regulatory filing Thursday.