Quote from peilthetraveler:
If anyone is interested in why I changed my bet from the $16 puts to the $19 puts, here is the reason. Math.
When the lockups expired in Aug (271 million shares) the stock dropped 6.3%.
When the lockups that expired in Oct(234 million shares) the stock dropped 5.02%.
1.2 billion shares will expire on the 14th. Subtract 60 million (Have to take zuckerbergs word that he wont sell) you have 1.14 billion shares.
1.14 billion/271 million = 4.2 times 6.3 = 26.5%
1.14 billion/234 million =4.87 times 5.02=24.45%
Of course, this is all things being equal which they never are. We dont know how many will panic if they see the stock drop 25% in the first 5 minutes of trading, nor do we know how many will start scooping up shares if they see the stock drop 25% in the first few minutes, but all things being equal, there is a reasonable probability that we can see around a 25% drop in FB stock on the 14th.
If FB stays at its current price of $21 until the 13th, we can expect the stock to probably drop to around the high $15s, low $16 range.