Warren Buffett (Trades, Portfolio)'s Berkshire Hathaway has made a significant addition to its holdings in Chevron Corp (NYSE:CVX), underscoring the firm's confidence in the energy sector. This transaction has brought Berkshire Hathaway's total share count in Chevron to 126,093,326, which now represents 5.96% of the firm's portfolio and 6.81% of Chevron's outstanding shares.