Facebook founder Mark Zuckerberg is following in the footsteps of tech philanthropist Bill Gates, donating half a billion dollars-worth of shares in the social network to charity.
It is the 28-year-old entrepreneur's second major donation since he pledged two years ago that he would give away most of his wealth. Mr Zuckerberg joined the Giving Pledge, a group founded by Mr Gates and billionaire investor Warren Buffett, which encourages America's mega-rich to donate at least half of their wealth.
Mr Zuckerberg announced his gift in a Facebook post, saying he and his wife Priscilla had, "in order to lay the foundation for new projects, made a contribution of 18 million Facebook shares to the Silicon Valley Community Foundation".
At current prices, Mr Zuckerberg's gift works out at $499m (£308m). In response, nearly 200,000 Facebook users "liked" his announcement.
Mr Zuckerberg, whose Facebook profile lists "minimalism" and "eliminating desire" as his interests, has a stake in vested Facebook shares worth about $11bn. In 2010 he donated $100m to rebuild public schools in Newark, New Jersey.
Meanwhile the Facebook-owned photo-sharing site Instagram has written to users clarifying its new terms and conditions that angered many and led them to close their accounts, saying: "We're listening... It is not our intention to sell your photos."