Most startup stock is not liquid. You'd have to sit on the stock until there's some sort of 'liquidity event' - usually the sale of the company or an IPO. Befor

Most startup stock is not liquid. You'd have to sit on the stock until there's some sort of 'liquidity event' - usually the sale of the company or an IPO. Beforehand sale of stocks is generally very difficult, usually not possible. I haven't really heard of companies buying back employee stocks (I guess they did it in 'Breaking Bad'? ;). If you get fired, and you don't want your stock options to expire worthless, assuming that they do expire, you'd have to exercise. And most likely you won't be able to sell that stock until a sale of the company or an IPO. The stock itself may also become worthless (bankruptcy). Note that the strike price really matters, some employee stock options are basically for free to exercise, because the strike price is very low. Sometimes the strike price is close to market value. If the strike price is low there may be a lot of taxes to pay, if it's high then you need to pay a lot for the stock itself. I'm not quite sure about silicon valley companies (I'm in Canada...). I've seen stock options expiring after 7 years or so. I've also heard of stock options that expire 3 weeks after the employment relationship. You should also be aware of the 'cliff period'. Most jobs won't give you proper stock options right away, but only after you have worked with them for a year. So if you quit after 10 months, you won't anything. Again, read your employment contracts (including stock option agreements), talk to a lawyer, inform yourself etc. Don't get burned by this stuff.