Evidence required by the assessor may include a copy or copies of that portion of the purchaser's or lessee's most recent filing under the United States Internal Revenue Code that indicates that the purchaser or lessee is engaged in commercial agricultural production, commercial fishing, commercial aquacultural production or commercial wood harvesting and that the purchased machinery or equipment is depreciable for those purposes or would be depreciable for those purposes if owned by the lessee.

In the event that any piece of machinery or equipment is only partially depreciable under the United States Internal Revenue Code, any reimbursement of the sales tax must be prorated accordingly. In the event that electricity or fuel for commercial agricultural production or a commercial fishing vessel is used in qualifying and nonqualifying activities, any reimbursement of the sales tax must be prorated accordingly.

Application for refunds must be filed with the assessor within 36 months of the date of purchase or execution of the lease.