I wouldn't advise this guy putting money into facebook just yet. A stock's price is supposed to reflect all information pertaining to a company (including a lock-up expiration). However, as with Groupon and LinkedIn, the price before their lock-ups expired didn't correctly reflect the value of the stock with all the 'unlocked' shares flooding the market.

I speculate that facebook's price will continue to go down post lock-up. Insiders aren't ignoring the poor news or outlook and I think they'll sell for more reasons than those. That's not necessarily because these insiders don't trust their company. They may have to pay off expensive things (maybe a nice home?) they bought when the company IPO'd and can't risk the uncertainty of facebook's future value. Also, if you ask any investor, they'll tell you that diversifying your portfolio is important.

Another interesting thing to think about are tax implications. I know a lot of facebook insiders were happy that their IPO was pre-July because otherwise, the lock-up would have crossed into 2013. This is when taxes on capital gains are expected to rise and it can cost them a lot of money.

I'm curious to see the performance of the stock in the coming months. Especially with the uncertainty of growth, possible tax increases, and the implications of the lock-up expiry, this will be an interesting journey for facebook.