(1) A plan of merger of a constituent limited liability company must be approved, and such approval shall occur when:

(a) The plan is approved by a majority of the members; and

(b) Any written consents required by RCW 25.15.456 have been obtained.

(2) Subject to RCW 25.15.456 and any contractual rights, after a merger is approved, and at any time before a filing is made under RCW 25.15.426, a constituent limited liability company may amend the plan or abandon the planned merger:

(a) As provided in the plan; and

(b) Except as prohibited by the plan, with the same approval as was required to approve the plan.

(3) If a domestic limited partnership is a party to the merger, the plan of merger must be adopted and approved as provided in RCW  25.10.781.

(4) If a domestic corporation is a party to the merger, the plan of merger must be adopted and approved as provided in chapter 23B.11 RCW.

(5) If a domestic partnership is a party to the merger, the plan of merger must be approved as provided in RCW 25.05.375.