Does forwarded mail need to be restamped?
If the message is remailed, then a new stamp is required since the sender’s address is included in the message hash. On the other hand, if the message is bounced (i.e., the header — including the sender address — and message body remain unchanged), then a new stamp is not required. This latter scenario is akin to use of blind carbon copy (bcc). See also Question 12. • Are there privacy implications in the fact that when a recipient verifies a stamp they learn how many times the stamp was previously verified? It is true that CentMail is giving the recipient a clue about the number of other recipients. If the sender wishes to fully conceal that information they should not stamp the message. Indeed, much of the point of stamping a message is to prove to the recipient that the message was not sent to them indiscriminately. • Who will run CentMail? Will there be competition for providing it? In addition to implementing CentMail ourselves (centmail.net), we are publishing the API as an ope
