Indiana Code Title 6. Taxation § 6-4.1-7-2

Sec. 2. A person who is dissatisfied with an appraisal made by the department of state revenue with respect to a resident decedent's estate may obtain a reappraisal of the property interest involved.  To obtain the reappraisal, the person must file a petition for reappraisal with the probate court within one (1) year after the department of state revenue enters an order determining the inheritance tax due as a result of the decedent's death.  However, if the original appraisal is fraudulently or erroneously made, the person may file the reappraisal petition within two (2) years after the department of state revenue enters the order.