Field: Investments, Berkshire Hathaway Inc.
Net worth:
$47 billion
Why he gave: "My wealth has come from a combination of living in America, some lucky genes, and compound interest…The reaction of my family and me to our extraordinary good fortune is not guilt, but rather gratitude. Were we to use more than 1 percent of my claim checks on ourselves, neither our happiness nor our well-being would be enhanced. In contrast, that remaining 99 percent can have a huge effect on the health and welfare of others. That reality sets an obvious course for me and my family: Keep all we can conceivably need and distribute the rest to society, for its needs."