Since Greg Abel took over from Warren Buffett as CEO at the beginning of the year, Berkshire Hathaway's public stock portfolio has seen a notable shift. Alphabet now ranks as a top-five position, and combined with Apple (which accounts for approximately 20.8%), the two tech companies make up about 31% of Berkshire's total stock holdings. Alphabet currently represents roughly 10.5% of the portfolio. Other top-five holdings include American Express, Coca-Cola, and Bank of America.