Billionaire Mark Zuckerberg and his wife, Priscilla Chan, are some of the biggest American philanthropists, according to reports.
Facebook co-founder Zuckerberg and his wife contributed 18 million shares of Facebook stock worth about $498.9 million to the Silicon Valley Community Foundation which works with education and health programs, according to the Chronicle of Philanthropy. The couple have a net worth of about $9.6 billion and ranked No. 2 on the 2012 philanthropy list. In 2010, Zuckerberg also donated $100 million in stock to Newark, N.J. schools.
The Zuckerberg-Chans were edged out by No. 1 on the list, Warren Buffett, who contributed $3.1 billion to various charitable foundations in 2012. Buffett is worth approximately $44 billion.
What people should know is that Zuckerberg did cash out last year in Facebook's initial public offering to the tune of $1.1 billion so he is legitimately a billionaire, but most of his contributions have been in Facebook stock. Facebook stock has been fairly volatile since its IPO in 2012, so it's not altogether as stable as cash.