Indiana Code Title 6. Taxation § 6-6-4.1-11

Sec. 11. (a) In lieu of filing individual reports under section 10 of this chapter, two (2) or more carriers regularly engaged in the transportation of passengers on through buses and through tickets in pooled service may make joint reports of their operations in Indiana.  The tax imposed by this chapter shall be calculated on the basis of the joint reports as though the carriers were a single carrier.  The carriers making the reports are jointly and severally liable for the tax.

(b) Joint reports made under subsection (a) must show the total number of miles traveled in Indiana and the total number of gallons of motor fuel purchased in Indiana by the reporting carriers.  Credits or refunds to which the carriers making a joint return are entitled are not allowed as credits or refunds to any other carrier.  Carriers filing joint reports shall permit all carriers engaged in pooled operations with them in Indiana to join them in filing joint reports.

(c) For purposes of this chapter, there is a rebuttable presumption that the vehicles of carriers filing joint reports consumed one (1) gallon of motor fuel for every six (6) miles traveled.