Oregon Revised Statutes Revenue and Taxation § 314.287

(1) In the computation of state taxable income, costs allocable to inventory shall be the same as those allocable to inventory under section 263A of the Internal Revenue Code   1 as of the close of the tax year for which a return is filed and shall not be adjusted for any addition, subtraction, modification or other adjustment contained in this chapter or ORS chapter 316, 317 or 318 or other law governing the imposition of state taxes imposed upon or measured by net income.

(2) If any provision of ORS chapter 316, 317 or 318 appears to require an adjustment to inventory costs contrary to the provisions of this section, that adjustment shall not be made.

(3) The additions, subtractions, modifications or other adjustments to federal taxable income required in determining Oregon taxable income under ORS chapter 316, 317 or 318 shall be made to federal taxable income notwithstanding that such adjustments are properly attributable to costs allocable to inventory.