Or. Rev. Stat. § 305.390

      305.390 Subpoenas of records containing information on industrial plant for use to determine value of different industrial plant. A subpoena for the production of records may be issued under ORS 305.190 or 305.420 to the owner of an industrial plant, as defined in ORS 308.408, for purposes of a proceeding involving the determination of the value of a different industrial plant for ad valorem property taxation, only under the following conditions:

      (1) The information to be produced is to be used to determine the value of a specific industrial plant;

      (2) The information to be produced is not available to the person or agency issuing the subpoena from any public source; and

      (3) The information to be produced is likely to improve the accuracy or reliability of the determination of value. [1993 c.353 §4]