RCW 25.10.711: Proper plaintiff.

A derivative action may be maintained only by a person that is a partner at the time the action is commenced and:

(1) That was a partner when the conduct giving rise to the action occurred; or

(2) Whose status as a partner devolved upon the person by operation of law or pursuant to the terms of the partnership agreement from a person that was a partner at the time of the conduct.