Washington Revised Code Title 11. Probate and Trust Law § 11.98.015. Noncharitable trusts without ascertainable beneficiaries

(1) A trust may be created for a noncharitable purpose without a definite or definitely ascertainable beneficiary or for a noncharitable but otherwise valid purpose to be selected by the trustee. The trust may not be enforced for longer than the time period specified in RCW 11.98.130 as the period during which a trust cannot be deemed to violate the rule against perpetuities;

(2) A trust authorized by this section may be enforced by a person appointed in the terms of the trust or, if no person is so appointed, by a person appointed by the court. Such person is considered to be a permissible distributee of the trust; and

(3) Property of a trust authorized by this section may be applied only to its intended use, except to the extent the court determines that the value of the trust property exceeds the amount required for the intended use. Except as otherwise provided in the terms of the trust, property not required for the intended use must be distributed to the trustor, if then living, otherwise to the trustor's successors in interest. Successors in interest include the beneficiaries under the trustor's will, if the trustor has a will, or, in the absence of an effective will provision, the trustor's heirs.