She donated 290,000 shares of Facebook stock at "a market value of roughly USD31 million" to various charities, according to a Securities and Exchange Commission document.

The shares were technically transferred to the Sheryl Sandberg Philanthropy Fund. The majority of the USD31 million donation will go to women's empowerment groups and Lean In, a nonprofit founded by Sandberg to help support women in the workplace, recode.net reported.

She also plans to give money to education groups and anti-poverty efforts.In December, Zuckerberg and Chan promised that they would give away their money "during our lives" through wealth charitable donations, private investment and promotion of government-policy reform.

Meanwhile, Facebook said in a securities filing Zuckerberg has planned to give away "no more than USD1 billion of Facebook stock each year for the next three years.