Sorry. Forgot to mention, I have an offer from one of them. Would it be a bad idea to try to negotiate the "non-negotiable" starting salary since the stocks and

Sorry. Forgot to mention, I have an offer from one of them. Would it be a bad idea to try to negotiate the "non-negotiable" starting salary since the stocks and signing bonus wouldn't be much use to me? (I need to be there for probably 4 or 5 years for all the bonus and stock stuff to be dispersed. I'd say about 25% of it would be dispersed before I went off to grad school without needing to be repaid.)