Berkshire's $299 billion very concentrated investment portfolio consists of 49 companies, unchanged from last quarter. Though it will take until fourth-quarter earnings are reported to get the final tally, it appears that Berkshire was a net seller of stocks during the quarter. The top 5 holdings account for over 75% of the total portfolio. The top five holdings, in order of the size of holding, are Apple AAPL (AAPL), Bank of America BAC (BAC), Chevron CVX (CVX CVX ), Coca-Cola (KO), and American Express AXP (AXP). Despite adding to Apple, it declined to almost 39% of its portfolio from about 42% in the third quarter. Due to these significant holdings plus Occidental Petroleum OXY (OXY) and Kraft Heinz (KHC), the portfolio is significantly overweight technology, energy, consumer staples, and financials relative to the S&P 500. Berkshire now controls more than 20% of the outstanding shares in Occidental. A deeper analysis of the probable reasons behind the Occidental purchase can be found here.