Wash. R. App. P. 18.23
As amended throough October 10, 2024
All briefs and other papers submitted to the Supreme Court and the Court of Appeals to be filed or considered in a case should be addressed to the clerk of the appropriate court and should clearly show, in the brief or paper itself or in a cover letter, (1) the name of the court to which the brief or paper is being submitted, (2) the caption of the case, and (3) the docket number of the case in the appellate court or, if none, the docket number of the case in the trial court and the name of the trial court.
A pleading will be considered timely filed by the Supreme Court and the Court of Appeals if it is timely filed in any Division of the Court of Appeals or in the Supreme Court.
Wash. R. App. P. RAP 18.23