While there are no hardandfastrules, option pools for early stage companies with high-growth potential often provide for a pool of option shares that would represent between 15%-20% of the total outstanding shares of the company.
These standards are hardandfastrules that make it impossible for, say, an airline-mechanic crew at LaGuardia Airport to give into the demands of impatient pilots and passengers when something appears to be not quite right with the landing gear on a departing plane.
And the tricky clinical particulars of any given resuscitation mean that the paper cannot give rise to hard-and-fast rules about exactly how long doctors should persist.