Comment by velominati

It is a misconception that when a company IPOs and the stock pops, that the delta is money left on the table. The vast majority of the shares are sold to institutional investors. There are explicit or implicit lock-up periods in place. And most of the pre-IPO investors will typically have a 6-month lockup. So if 10% of shares are sold in the IPO and 10% of those shares are actually trade-able, only 1% of the total stock is liquid. That can lead to very large price swings (i.e. the pop).