Mark Zuckerberg, founder and CEO of Facebook (NYSE: FB), is selling 41.4 million shares of his own class A Facebook stock as part of a pubic offering of 70 million shares. Zuckerberg will use the proceeds from this sale — expected to be about $3.9 billion — to pay off a liability incurred when he exercised an option to purchase 60 million B shares of common stock. But don???t worry for a second that these transactions will weaken Zuckerberg???s position personally or professionally. On the personal side, Facebook???s CEO watched his A shares double in price this year. While on the professional side, the sale of his A shares only slightly reduced his voting power from 58.8 percent to 56.1 percent. And finally, for independent investors like you and me, these transactions ended up taking Facebook???s share price down 4 percent yesterday, to close at $53.54.