A digital stamp is a unique forensic key that EchoMark can embed in every document and message shared via EchoMark. We add these to documents and messages using different proprietary methods designed to be difficult to detect and/or tamper with. A digital stamp can be detected within a leaked PDF or .EML file, but is not detectable in a screenshot, photo, or leaked text - for those scenarios, check out our Invisible Watermark.