Wash. Rev. Code § 26.26A.400 : DOMESTIC RELATIONS — Uniform parentage act — Proceeding to Adjudicate Parentage —PROCEEDING TO ADJUDICATE PARENTAGE Nature of Proceeding — Proceeding to adjudicate parentage-Authorization
(1) A proceeding may be commenced to adjudicate the parentage of a child. Except as otherwise provided in this chapter, the proceeding is governed by the rules of civil procedure.
(2) A proceeding to adjudicate the parentage of a child born under a surrogacy agreement is governed by
RCW 26.26A.700 through
26.26A.785.