The Bill & Melinda Gates Foundation Trust holds its largest portfolio position in Berkshire Hathaway, not Microsoft, which ranks as its fifth-largest holding. Approximately 30% of the trust's $36 billion portfolio is invested in Berkshire Hathaway stock.
As of its most recent 13F filing, the trust owned nearly 21.8 million shares of Berkshire Hathaway, valued at over $10.9 billion. In the third quarter of 2025, the trust sold 2.36 million shares of Berkshire, reducing its position by almost 9.8%.
Warren Buffett led Berkshire Hathaway for over six decades before recently passing the CEO role to Greg Abel. Buffett remains Berkshire's chairman and its largest shareholder. The Gates Foundation Trust is also a major shareholder in the conglomerate.
Between 1964 and 2024, Berkshire Hathaway delivered an overall gain of 5,502%, translating to a compound annual growth rate of 19.9%. During the same period, the S&P 500's compounded annual gain was 10.4%.
Bill Gates and Warren Buffett have been friends for years. Gates served on Berkshire's board of directors from 2004 to 2020, and Buffett previously served on the Gates Foundation's board.
Berkshire Hathaway continues to generate strong free cash flow. Its wholly owned businesses and stakes in other publicly traded companies are diversified across multiple sectors and industries.