Thank you for you interest in the University of Texas Health Science Center at Houston. Sincerely,. Name. Title. Enclosure. 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. This typically means the signer must personally appear before the Notary and be properly identified, and sign, or acknowledge signing, the document. An Acknowledgment of Paternity (AOP) is a legal document that allows parents who aren't married to establish legal paternity. Instructions to send a certified letter, return receipt requested. MV-531.