2013 ORS § 130.235¹
In terrorem clause

(1) Except as provided in this section, an in terrorem clause in a trust is valid and enforceable. If a beneficiary challenges a trust that contains an in terrorem clause that applies to the beneficiary, the court shall enforce the clause against the beneficiary even though the beneficiary establishes that there was probable cause for the challenge.

(2) The court shall not enforce an in terrorem clause if the beneficiary challenging the trust establishes that the beneficiary has probable cause to believe that the trust is a forgery or that the trust has been revoked.

(3) The court shall not enforce an in terrorem clause if the challenge is brought by a fiduciary acting on behalf of a protected person under the provisions of ORS chapter 125, a guardian ad litem appointed for a minor or a guardian ad litem appointed for an incapacitated or financially incapable person.

(4) For the purposes of this section, in terrorem clause means a provision in a trust that reduces or eliminates the interest of a beneficiary under the trust if the beneficiary challenges the validity of part or all of the trust. [2005 c.348 §38]