Oregon Revised Statutes Remedies and Special Actions and Proceedings § 31.600

(1) Contributory negligence shall not bar recovery in an action by any person or the legal representative of the person to recover damages for death or injury to person or property if the fault attributable to the claimant was not greater than the combined fault of all persons specified in subsection (2) of this section, but any damages allowed shall be diminished in the proportion to the percentage of fault attributable to the claimant. This section is not intended to create or abolish any defense.

(2) The trier of fact shall compare the fault of the claimant with the fault of any party against whom recovery is sought, the fault of third party defendants who are liable in tort to the claimant, and the fault of any person with whom the claimant has settled. The failure of a claimant to make a direct claim against a third party defendant does not affect the requirement that the fault of the third party defendant be considered by the trier of fact under this subsection. Except for persons who have settled with the claimant, there shall be no comparison of fault with any person:

(3) A defendant who files a third party complaint against a person alleged to be at fault in the matter, or who alleges that a person who has settled with the claimant is at fault in the matter, has the burden of proof in establishing:

(4) Any party to an action may seek to establish that the fault of a person should not be considered by the trier of fact by reason that the person does not meet the criteria established by subsection (2) of this section for the consideration of fault by the trier of fact.

(5) This section does not prevent a party from alleging that the party was not at fault in the matter because the injury or death was the sole and exclusive fault of a person who is not a party in the matter.