Indiana Code Title 6. Taxation § 6-6-2.5-29

Sec. 29. (a) Persons having title to special fuel in storage and held for sale on the effective date of an increase in the license tax rate imposed under section 28 of this chapter are subject to an inventory tax based on the gallons in storage as of the close of the business day preceding the effective date of the increased license tax rate.

(b) Persons subject to the tax imposed under this section shall:

In determining the amount of special fuel tax due under this section, the person may exclude the amount of special fuel that will not be pumped out of the storage tank because the special fuel is below the mouth of the draw pipe.  For this purpose, the person may deduct two hundred (200) gallons for a storage tank with a capacity of less than ten thousand (10,000) gallons, and four hundred (400) gallons for a storage tank with a capacity that exceeds ten thousand (10,000) gallons.

(c) The amount of the inventory tax is equal to the inventory tax rate times the gallons in storage as determined under subsection (b).  The inventory tax rate is equal to the difference of the increased license tax rate minus the previous license tax rate.

(d) The inventory tax shall be considered a listed tax for the purposes of IC 6-8.1.