It's worth noting that most startups nowadays also include a non-transference clause in the options contract. This forbids any private sale of shares outside of

It's worth noting that most startups nowadays also include a non-transference clause in the options contract. This forbids any private sale of shares outside of a liquidity event. This is terrible for an employee leaving a company. Not only is the employee on the hook for a big tax bill if he exercises, but he can't even sell any of his shares to cover the cost. AFAIK, this is a response to Facebook employees selling equity on private markets.