Or. R. App. P. 5.77

As amended through January 17, 2024
Rule 5.77 - JOINT AND ADOPTED BRIEFS
(1) In a case involving more than one party on the same side, including cases consolidated on appeal, the court discourages the filing of briefs that duplicate arguments made in another brief in the same case and encourages parties to file joint briefs or to adopt to the extent practicable a brief filed by another party in the same case.
(2) A party may join or adopt a brief submitted in the same case or consolidated case but shall not join or adopt a brief in another case.
(3) Joint Briefs
(a) If two or more parties join in a brief by signing the brief and have not previously appeared and paid a filing fee, only one filing fee need be paid.
(b) A party who has not signed a brief filed by another may join that brief provided that the party:
(i) Obtains the consent of the party who filed the brief;
(ii) Pays a filing or first appearance fee; and
(iii) Submits a letter to the court copied to all parties on appeal stating that the party joins in the brief filed by another party and has the consent of the other party.
(4) Adopted Briefs
(a) A party who concurs with all or part of a brief filed by another party and who has no other position to assert may adopt the other party's brief by filing a brief adopting in whole or in part the brief of another party. If a party adopts only part of the brief of another, the brief shall identify the part of the brief of the other party being adopted.
(b) A party who concurs with all or part of a brief submitted by another party but who wishes to argue additional matters may submit a brief adopting by reference the part of the other party's brief in which the party concurs.

Or. R. App. P. 5.77