Survey: Buffett Gave Biggest Charitable Contribution of 2014

Buffett, CEO of Berkshire Hathaway, donated $2.1 billion to the Bill and Melinda Gates Foundation in the form of 16.6 million Berkshire shares. That was 3 percent of his net worth.

The list consists entirely of Americans, except for Hong Kong real estate moguls Ronnie and Gerald Chan (brothers). Together they gave $350 million to Harvard, the single biggest gift in its history.

Ken Griffin, founder of hedge fund manager Citadel, also donated to Harvard: $150 million, or 3 percent of his net worth.

Nicholas Woodman, founder of GoPro, donated $497.5 million, or 10 percent of his net worth, to the Silicon Valley Community Foundation.

Gert Boyle, chairwoman of Columbia Sportswear, gave $100 million, or 16 percent of her net worth, to Oregon Health & Science University.

And John Morgridge, former CEO of Cisco Systems, donated $100 million, or 6 percent of his net worth, to the University of Wisconsin.

Meanwhile, billionaire Michael Bloomberg, former mayor of New York City, says his ultra-wealthy brethren must be realistic in their philanthropy. They can't adopt the attitude that they will solve the world's problems by themselves, he told The New York Times.

"All the billionaires added together are, as they’d say, bupkis compared to the amount of money that government spends," he said. "It’s trillions of dollars. Private philanthropy can’t do that."

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