In Private Letter Ruling ST 15-0016-PLR, the Illinois Department of Revenue explained the application of the temporary storage exemption to the imposition of use tax on the in-state storage of equipment. Illinois’ temporary storage exemption applies where the property is acquired outside Illinois and, after a temporary stay in the state, is shipped out of and used solely outside of Illinois. First, the temporary storage exemption applies when a customer orders equipment from the taxpayer that it acquires from outside of Illinois, the customer requests that the taxpayer store the equipment in the taxpayer’s Illinois warehouse for a period of time, the customer is invoiced and the title transfers after the equipment arrives at the Illinois warehouse, and the taxpayer ships the equipment to the out-of-state customer via common carrier. Second, the exemption does not apply when the taxpayer orders the equipment based instead on an internal forecast or per customer instructions, places the equipment in its inventory when it arrives at the Illinois warehouse, invoices the customer and transfers title if the customer has not requested shipment within 180 days, and ships the equipment only after receiving further instructions from the customer. However, the interstate commerce exemption applies because the taxpayer is obligated to physically deliver the goods from a point in Illinois to a point outside of Illinois, not to be returned to a point within Illinois, as long as delivery is actually made. Third, the temporary storage exemption applies when the taxpayer acquires the equipment from outside of Illinois, the property is shipped to and stored at the Illinois warehouse temporarily, the taxpayer performs services on the equipment, and the product is stored at the warehouse until the customer provides instructions for shipment out-of-state. Ill. Private Letter Ruling No. ST 15-0016-PLR, Ill. Dep’t of Revenue (issued Nov. 13, 2015).