ORS 305.780: Taxes due prior to year in which suit brought.

Nothing contained in ORS 305.770 to 305.785 authorizes the refunding of any tax collected and paid under an invalidated tax law, or invalidated part thereof, where the tax as provided in such law became due and payable in any year prior to the year in which the suit or action seeking the invalidation of the law or part thereof was instituted.