Since the Citizens United declaration that Corporations are indeed people, it is only fair that they be forced to follow he tax rate for individuals.
A small business owner who pays his bills out of his own pocket has to pay a 39.6% rate if he goes over income of $450K.
But a multi-national corporation making $4B pays an effective rate of less than 25%. They are able to use their vast wealth to act as people in the choice of our elected officials so they can share in the burden of paying for their work.
These small business owners are forced to survive by their business model not moving funds to get tax breaks or moving operations to avoid them entirely.