Oregon Revised Statutes Revenue and Taxation § 319.390

Every dealer in motor vehicle fuel shall keep a record in such form as may be prescribed by the Department of Transportation of all purchases, receipts, sales and distribution of motor fuel. The records shall include copies of all invoices or bills of all such sales and shall at all times during the business hours of the day be subject to inspection by the department or its deputies or other officers duly authorized by the department. Upon request from the officials to whom is entrusted the enforcement of the motor fuel tax law of another state, territory, country or the federal government, the department shall forward to such officials any information which it may have relative to the import or export of any motor vehicle fuel by any dealer, provided such other state, territory, country or federal government furnishes like information to this state.