1.2 billion shares in locks up expire then. Has there ever been a company in history where 50% of all the outstanding shares were unlocked on a single day? Even if zuckerberg keeps his promise and doesnt sell till sept. 2013, its still what...800 million shares that are potentially going on the market that day? As of right now Nov $16 put options are asking .05. A $100 spec bet could potentially net you $12,000.