Wash. Rev. Code § 36.28.050
If any property levied upon by virtue of any writ of attachment or execution or other order issued to the sheriff out of any court in this state is claimed by any person other than the defendant, and such person or his or her agent or attorney makes affidavit of his or her title thereto or his or her right to possession thereof, stating the value thereof and the basis of such right or title, the sheriff may release such levy, unless the plaintiff on demand indemnifies the sheriff against such claim by an undertaking executed by a sufficient surety.
No claim to such property by any person other than the defendant shall be valid against the sheriff, unless the supporting affidavit is made. Notwithstanding receipt of a proper claim the sheriff shall retain such property under levy a reasonable time to demand such indemnity.
Any sheriff, or other levying officer, may require an indemnifying bond of the plaintiff in all cases where he or she has to take possession of personal property.
RCW 36.28.050