Systems and methods for authenticating the mailer of a mail piece in a manner that is trustworthy and not easily susceptible to fraudulent manipulation are provided. A mail processing system is utilized by recipients of mail pieces to scan each incoming mail piece. The mail processing system obtains information from the mail piece, which can include an identification of the postage meter that was used to generate the indicium. Based on the identification of the postage meter or other unique information, the recipient's mail processing system can obtain an identification of the mailer. Once the identification of the mailer is ascertained based on this information, the recipient can utilize one or more business rules for internal delivery of the mail piece.