Ind. Code § 6-1.1-51-12

Sec. 12. To qualify for the deduction, the taxpayer must claim the deduction, in the manner prescribed by the department of local government finance, on the taxpayer's personal property tax return filed under IC 6-1.1-3 or IC 6-1.1-8 (or an amended return filed within the time allowed under this article) for the abated property to which the deduction applies.