Comment by the_wheel

I was in a very similar situation 6 months ago. If you have a typical agreement in place (4 yr vesting schedule w/ an initial 1 yr cliff), about 10% is not only reasonable, it's what you're legally entitled to. If you're legally entitled to 10% and you believe the company is going to increase in value and eventually exit without you, it would be foolish to sell then your stake.