The charities usually sell the Berkshire shares to finance their activities, reflecting Buffett's desire that his money be spent. Buffett also makes smaller donations to other charities.
Berkshire has roughly 90 subsidiaries including Geico car insurance, the BNSF railroad and Dairy Queen ice cream, and has large stakes in companies such as Kraft Heinz Co, Wells Fargo & Co, Coca-Cola Co and IBM Corp.
Buffett has run Berkshire since 1965.