Mark Zuckerberg sold $357 million worth of Facebook shares this month, ramping up his regularly timed stock selling to fund his philanthropic efforts.
Zuckerberg said in September he would sell 35 million to 75 million shares during the following 18 months to help fund the philanthropic Chan Zuckerberg Initiative.
The planned sales, worth $6 billion to $12.5 billion when announced, would be worth up to $13 billion at the stock's current price near $185 a share.
According to Zuckerberg's latest statement of stock ownership, filed earlier this month, he still controls 87 percent of Facebook voting shares.
Facebook shares was trading at $184.64 a share Monday afternoon.