They’re not donating large amounts in cash. A great example is the Bill and Melinda Gates Foundation, which holds about 11 **Billion** dollars worth of Berkshire Hathaway stock (well, probably less after this week…).
Warren Buffet wanted to donate a large portion of his net worth, so over the years he’s gifted the foundation shares of his company. When the foundation needs money for project, they simply sell as many shares as they need to pay for it.
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