N.J. Stat. § 54:38-3
If, subsequent to the determination of the tax due under this chapter, the amount of the Federal estate tax shall be decreased and the amount of the Federal credit correspondingly reduced by reason of any corrected assessment or redetermination, the tax due hereunder shall be reduced accordingly upon satisfactory proof submitted to the State Tax Commissioner, and, if the tax due hereunder shall have theretofore been paid into the State treasury, the Comptroller of the Treasury, on satisfactory proof of such fact submitted to the State Tax Commissioner, and duly certified by him to the Comptroller, shall draw his warrant on the State Treasurer in favor of the executor, administrator, trustee, person or corporation who has paid said tax, or who may be lawfully entitled to receive the same, for the amount of such tax excessively paid and said warrant shall be paid by the State Treasurer out of any appropriation for the refund of transfer inheritance taxes the same as warrants for the refund of such taxes under the transfer inheritance tax statutes of this State are paid. The foregoing provisions respecting refund shall apply with the same force and effect to any other payments determined by the State Tax Commissioner to have been excessively made under this chapter.
All applications for the refund of taxes claimed to have been excessively or erroneously paid hereunder must be filed with the State Tax Commissioner within three years from the date of payment.
N.J.S. § 54:38-3