What is a U.S. Postal Service® (USPS) Electronic Postmark® (EPM®) seal?
The EPM® seal is a content integrity and time-and-datestamp seal that can be applied to any form of electronic content or transaction record, which can be used to verify the authenticity of the electronic content or transaction at a subsequent point in time. Once an EPM® seal is applied to a document, it may be utilized as proof that a document existed in that form as of a specified point in time. The EPM® seal information is stored by Authentidate for up to seven years from date of application. The U.S. Postal Service® defines and maintains the technical and operational standards for EPM® service provision, and will provide backup support to verify all seals applied.
