Sources:
[1] Zuckerberg has sold more Facebook stock in the last 3 months than any insider at any other company => https://www.cnbc.com/2018/03/20/zuckerbergs-facebook-stock-s...
[2] Zuckerberg saved tens of millions of dollars by selling Facebook stock ahead of Monday’s decline: https://www.marketwatch.com/story/zuckerberg-saved-tens-of-m...