Wash. Rev. Code § 64.04.070
Whenever any person or persons having sold and conveyed by deed any lands in this state, and who, at the time of such conveyance, had no title to such land, and any person or persons who may hereafter sell and convey by deed any lands in this state, and who shall not at the time of such sale and conveyance have the title to such land, shall acquire a title to such lands so sold and conveyed, such title shall inure to the benefit of the purchasers or conveyee or conveyees of such lands to whom such deed was executed and delivered, and to his or her and their heirs and assigns forever. And the title to such land so sold and conveyed shall pass to and vest in the conveyee or conveyees of such lands and to his or her or their heirs and assigns, and shall thereafter run with such land.
RCW 64.04.070