2011 ORS § 109.070¹
(1) The paternity of a person may be established as follows:
(a) A man is rebuttably presumed to be the father of a child born to a woman if he and the woman were married to each other at the time of the childs birth, without a judgment of separation, regardless of whether the marriage is void.
(b) A man is rebuttably presumed to be the father of a child born to a woman if he and the woman were married to each other and the child is born within 300 days after the marriage is terminated by death, annulment or dissolution or after entry of a judgment of separation.
(c) By the marriage of the parents of a child after the birth of the child, and the parents filing with the State Registrar of the Center for Health Statistics the voluntary acknowledgment of paternity form as provided for by ORS 432.287 (Voluntary acknowledgment of paternity form).
(d) By filiation proceedings.
(e) By filing with the State Registrar of the Center for Health Statistics the voluntary acknowledgment of paternity form as provided for by ORS 432.287 (Voluntary acknowledgment of paternity form). Except as otherwise provided in subsections (4) to (7) of this section, this filing establishes paternity for all purposes.
(f) By having established paternity through a voluntary acknowledgment of paternity process in another state.
(g) By paternity being established or declared by other provision of law.
(2) The paternity of a child established under subsection (1)(a) or (c) of this section may be challenged in an action or proceeding by the husband or wife. The paternity may not be challenged by a person other than the husband or wife as long as the husband and wife are married and cohabiting, unless the husband and wife consent to the challenge.
(3) If the court finds that it is just and equitable, giving consideration to the interests of the parties and the child, the court shall admit evidence offered to rebut the presumption of paternity in subsection (1)(a) or (b) of this section.
(4)(a) A party to a voluntary acknowledgment of paternity may rescind the acknowledgment within the earlier of:
(A) Sixty days after filing the acknowledgment; or
(B) The date of a proceeding relating to the child, including a proceeding to establish a support order, in which the party wishing to rescind the acknowledgment is also a party. For the purposes of this subparagraph, the date of a proceeding is the date on which an order is entered in the proceeding.
(b) To rescind the acknowledgment, the party shall sign and file with the State Registrar of the Center for Health Statistics a written document declaring the rescission.
(5)(a) A signed voluntary acknowledgment of paternity filed in this state may be challenged and set aside in circuit court at any time after the 60-day period referred to in subsection (4) of this section on the basis of fraud, duress or a material mistake of fact.
(b) The challenge may be brought by:
(A) A party to the acknowledgment;
(B) The child named in the acknowledgment; or
(C) The Department of Human Services or the administrator, as defined in ORS 25.010 (Definitions for support enforcement laws), if the child named in the acknowledgment is in the care and custody of the department under ORS chapter 419B and the department or the administrator reasonably believes that the acknowledgment was signed because of fraud, duress or a material mistake of fact.
(c) The challenge shall be initiated by filing a petition with the circuit court. Unless otherwise specifically provided by law, the challenge shall be conducted pursuant to the Oregon Rules of Civil Procedure.
(d) The party bringing the challenge has the burden of proof.
(e) Legal responsibilities arising from the acknowledgment, including child support obligations, may not be suspended during the challenge, except for good cause.
(f) If the court finds by a preponderance of the evidence that the acknowledgment was signed because of fraud, duress or material mistake of fact, the court shall set aside the acknowledgment unless, giving consideration to the interests of the parties and the child, the court finds that setting aside the acknowledgment would be substantially inequitable.
(6) Within one year after a voluntary acknowledgment of paternity form is filed in this state and if blood tests, as defined in ORS 109.251 (Blood tests defined), have not been completed, a party to the acknowledgment, or the department if the child named in the acknowledgment is in the care and custody of the department under ORS chapter 419B, may apply to the administrator for an order for blood tests in accordance with ORS 416.443 (Reopening issue of paternity).
(7)(a) A voluntary acknowledgment of paternity is not valid if, before the party signed the acknowledgment:
(A) The party signed a consent to the adoption of the child by another individual;
(B) The party signed a document relinquishing the child to a public or private child-caring agency;
(C) The partys parental rights were terminated by a court; or
(D) In an adjudication, the party was determined not to be the biological parent of the child.
(b) Notwithstanding any provision of subsection (1)(c) or (e) of this section or ORS 432.287 (Voluntary acknowledgment of paternity form) to the contrary, an acknowledgment signed by a party described in this subsection and filed with the State Registrar of the Center for Health Statistics does not establish paternity and is void. [1957 c.411 §2; 1969 c.619 §11; 1971 c.127 §2; 1975 c.640 §3; 1983 c.709 §37; 1995 c.79 §37; 1995 c.514 §7; 1999 c.80 §20; 2001 c.455 §17; 2003 c.576 §136; 2005 c.160 §§11,17; 2007 c.454 §1]