Warren Buffett acquired 533 Thousand Amazon.com shares worth $1.21 Billion. That's 0.4% of their equity portfolio (22nd largest holding). Warren Buffett started to build up the position in Amazon.com in Q1 2019 and continued to invest until Q2 2019. Since then they sold 4 Thousand shares. The stake costed the investor $898 Million, netting the investor a gain of 34% so far.