Ind. Code § 6-2.5-3-7
(c) A retail merchant that sells tangible personal property to a person that purchases the tangible personal property for use or consumption in providing public transportation under IC 6-2.5-5-27 may verify the exemption by obtaining the person's:
(3) motor carrier number, United States Department of Transportation number, or any other identifying number authorized by the department.
The person engaged in public transportation shall provide a signature to affirm under penalties of perjury that the information provided to the retail merchant is correct and that the tangible personal property is being purchased for an exempt purpose.
As added by Acts 1980, P.L.52, SEC.1. Amended by P.L.211-2007, SEC.10.