Facebook founder Mark Zuckerberg topped the list of US philanthropists who opened their cheque books to make big donations in 2013, with his gift of almost $1 billion to a Silicon Valley charity.
Mr Zuckerberg and Priscilla Chan, his wife, gave 18 million Facebook shares worth about $990 million to the Silicon Valley Community Foundation in December, nearly 30 per cent of the $3.4 billion total given to charity last year.
The gift – to a charity which works to support the neighbourhood where Facebook has its headquarters – marks the first time a philanthropist under the age of 30 has given the largest single donation.
The year also saw a rise in the number of donations of more than $100 million, with 14 US citizens including Michael Bloomberg and David Koch giving at least that sum, according to the Chronicle of Philanthropy, which compiled the list. This compares with 11 who gave more than $100 million in 2012.
Stacy Palmer, the Chronicle's editor, said the rise in large gifts was a sign of the improvement in the economy and the stock market. She said it made her "optimistic" that 2014 could be a strong year for philanthropy.
"I think this is a good sign. I've noticed a lot of non-profits saying their end of year fundraising has gone well, which was not the case in the past few years when it was a real struggle," she said.
(Read more: The great Google, Facebook and Apple cash pile)
But gifts are not yet back to the level seen before the recession, with a total of $4.1 billion donated in 2007.
Mr Zuckerberg is "remarkably young" for such a large donation, which follows another gift of shares worth $500 million to the same foundation last year, Ms Palmer said.
"One of the things that is interesting about the Zuckerberg gifts is he is giving to a community foundation which supports lots of different causes, instead of setting up his own foundation in his name . . . like Gates, Carnegie or Rockefeller," she said.
Mr Zuckerberg's donation comes at a time of tension between the technology industry and other communities in the Bay Area, some of which have protested about the affluent tech workers pushing up rents.
Ms Palmer added other technology billionaires were also making large donations, often focusing on education or scientific advances, but many preferred to give anonymously.
Phil Knight, chairman of Nike, and his wife were the second-largest givers in the US in 2013 with their pledge of $500 million to the Oregon Health & Science University Foundation for cancer research.
Mr Knight was followed by Michael Bloomberg, former mayor of New York, who pledged $350 million to his alma mater, Johns Hopkins University, to promote cross-disciplinary work and for student financial aid.
Colleges and universities were the main beneficiaries of large donations in 2013 with 12 of the 15 leading gifts going to higher education. Charles Johnson, the financier, pledged $250 million to Yale University for new buildings, while Stephen Ross, the real estate developer, pledged $200 million to the University of Michigan.
Other recipients included Stanford University, Columbia Business School and Tsinghua University in Beijing.
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