Oregon Revised Statutes Domestic Relations § 109.381

(1) A judgment of a court of this state granting an adoption, and the proceedings in such adoption matter, shall in all respects be entitled to the same presumptions and be as conclusive as if rendered by a court of record acting in all respects as a court of general jurisdiction and not by a court of special or inferior jurisdiction, and jurisdiction over the persons and the cause shall be presumed to exist.

(2) Except for such right of appeal as may be provided by law, judgments of adoption shall be binding and conclusive upon all parties to the proceeding. No party nor anyone claiming by, through or under a party to an adoption proceeding, may for any reason, either by collateral or direct proceedings, question the validity of a judgment of adoption entered by a court of competent jurisdiction of this or any other state.

(3) After the expiration of one year from the entry of a judgment of adoption in this state the validity of the adoption shall be binding on all persons, and it shall be conclusively presumed that the child's natural parents and all other persons who might claim to have any right to, or over the child, have abandoned the child and consented to the entry of such judgment of adoption, and that the child became the lawful child of the adoptive parents or parent at the time when the judgment of adoption was rendered, all irrespective of jurisdictional or other defects in the adoption proceeding. After the expiration of the one-year period no one may question the validity of the adoption for any reason, either through collateral or direct proceedings, and all persons shall be bound thereby. However, the provisions of this subsection shall not affect the right of appeal from a judgment of adoption as may be provided by law.