Zuckerberg to Be Taxed at Lower Rate Than Most Facebook Employees
mashable.com
mashable.com
I am quite knowledgeable in finance, but am Canadian and in Canada all stocks are taxed as capital gains and all capital gains are taxed at 25%.
We do have a complication when it comes to distribuited dividends, but I imagine so do the States.
However, even if you 'exercise' your stock options at IPO (buy stocks for the price of the valuation when they were granted to you), you don't have to cash in your stocks, which means that the gains would not be realized (and thus not taxable) until you do.
The tax, however, would be the same as any other capital gains, which is 25%. We do not care how long the gain took to realize, just the fact that the net gain was positive. (You can carry capital losses from the previous years and offset your positive capital gains when you have them.)