Ind. Code § 6-4.1-6-6
(b) The inheritance tax imposed on the decedent's transfer of a contingent or defeasible interest in property accrues and is due when the transferee of the interest obtains the beneficial enjoyment or possession of the property if the fair market value of the property interest as of the appraisal date prescribed by IC 6-4.1-5-1.5 cannot otherwise be ascertained under this chapter.
As added by Acts 1976, P.L.18, SEC.1. Amended by Acts 1980, P.L.57, SEC.18; P.L.190-2016, SEC.18.