This is not true in most contracts - you can negotiate for it if you're high enough level or early enough, but otherwise it's rarely the case. Besides, if you

This is not true in most contracts - you can negotiate for it if you're high enough level or early enough, but otherwise it's rarely the case. Besides, if you get fired from a startup and it's not for cause, then it's probably because there are layoffs, so it might be a bad choice to exercise your options anyway.