Washington Revised Code Title 4. Civil Procedure § 4.56.090. Assignment of judgment--Filing

When any judgment has been assigned, the assignment may be filed in the office of the county clerk in the county where the judgment is recorded and a certified copy thereof may be filed in any county where an abstract of such judgment has been filed and from the time of such filing shall be notice of such assignment: PROVIDED, That such assignment of a judgment or such certified copy thereof, may not be filed unless it is properly acknowledged before an officer qualified by law to take acknowledgment of deeds.