An acknowledgment is one of the most common types of notarial acts, but it often confuses Notaries. Here are 5 steps to performing an acknowledgment.For an acknowledgment in a representative capacity: State of Washington. The short-form acknowledgment certificate is used when an individual is signing and acknowledging on his or her own behalf. A Washington notary acknowledgment form lets a notary public confirm the legitimacy of the signing party's signature and prevents forgery on legal documents. A Washington notary acknowledgment form is used to officially authenticate a signature on a legal document. This 5-step guide will teach you how to notarize a document that requires an acknowledgement (the most common notarial act).