Facebook chief operating officer Sheryl Sandberg on Friday joined the club of billionaire philanthropists founded by Warren Buffet and Bill and Melinda Gates, who have all promised to give away half of their fortunes.
Others among the seven new signatories announced by the group, Giving Pledge, were Kinko's founder Paul Orfalea and one of Google's first employees, Craig Silverstein.
"They bring a wealth of expertise to the group. We will learn a lot from their experiences as we collectively aim to inspire one another to earlier and better giving," Buffet said.
The Seattle-based global campaign encourages billionaires to give away at least half their fortunes to charitable causes.
U.S. magazine Forbes estimates Sandberg's net worth to be about 949.9 million dollars.
The Giving Pledge has a total of 127 signatories representing 12 countries and 26 US states.
Other famous participants include Microsoft co-founder Paul Allen, Facebook's Mark Zuckerberg and Star Wars creator George Lucas.