(A) A tax is imposed upon every generation-skipping transfer, where the original transferor is a resident of this State at the date of original transfer, in an amount equal to the maximum amount allowable as a credit for state generation-skipping transfer taxes under Internal Revenue Code Section 2604, to the extent the credit exceeds the aggregate amount of all taxes on the same transfer actually paid to the several states of the United States, other than this State.

(B) A tax is imposed upon every generation-skipping transfer where the original transferor is not a resident of this State at the date of the original transfer, but where the generation-skipping transfer includes real or personal property having a situs in this State, in an amount equal to the maximum amount allowable as a credit for state generation-skipping transfer taxes under Internal Revenue Code Section 2604, reduced by an amount which bears the same ratio to the total state tax credit allowable for federal generation-skipping transfer tax purposes as the value of the transferred property taxable by all other states bears to the value of the gross generation-skipping transfer for federal generation-skipping transfer tax purposes. In any case in which a tax is imposed on a generation-skipping transfer by this State and by one or more other states, the department shall negotiate with the taxing authorities of the other state or states so that the aggregate amount of taxes imposed by this State and the other state or states on a generation-skipping transfer does not exceed one hundred percent of the maximum amount allowable as credit for state generation-skipping transfer taxes under Internal Revenue Code Section 2604.