ORS § 316.047
If any provision of the Internal Revenue Code or of this chapter requires that any amount be added to or deducted from federal gross income or the net income taxable under this chapter that previously had been added to or deducted from net income taxable under the Oregon law in effect prior to the taxpayer's taxable year as to which this chapter is first effective, then, in such event, appropriate adjustment shall be made to the net income for the year or years subject to this chapter so as to prohibit the double taxation or the double deduction of any such amount that previously had entered into the computation of taxable income. Differences such as the difference in basis of property used by the taxpayer for federal and Oregon income tax returns and on account of the treatment of operating losses shall be resolved by application of this principle. However, the Department of Revenue, in its audit of a return, shall not apply any adjustment under this section which, in its opinion, if applied would result in an increase or decrease of tax liability of less than $25.
ORS 316.047