A Washington notary acknowledgment form is used to officially authenticate a signature on a legal document. State of Washington.Download a notary acknowledgment form in PDF or Word format. Fill out, sign, and affix your official seal to the Notary certificate. The wording requirements for acknowledgment certificates vary from state to state. The Washington Notary Acknowledgement forms are documents used to prove the validity of a signature on a legal document. Edit, sign, and share sample acknowledgement receipt online. No need to install software, just go to DocHub, and sign up instantly and for free. Enter your full name in the designated field. If you are served on behalf of another person and you are authorized to receive process, you must indicate under your signature your authority.