US 7865557

Patent Overview — US 7,865,557 B2

Title: System and method for verifying delivery and integrity of electronic messages

Patent number: US7865557B2 | Application: US11/725,210 | Filed: 2007-03-16 | Granted/Published: 2011-01-04 | Priority date: 1999-07-28 | Inventor: Terrance A. Tomkow | Original assignee: RPost International Ltd | Current assignee (as listed): Rpost Communications Ltd | Status: Expired – Lifetime, adjusted expiration 2020-10-30.

Purpose. The patent addresses a long-recognized problem: ordinary e-mail receipts are weak evidence because they "may be just another e-mail message that could have been altered or created by anyone, at any time." The stated object is to "reliably verify[] via secure and tamper-proof documentation the content and delivery of an electronic message such as an e-mail," giving e-mail "a legal status on a par with, if not superior to, that of registered United States mail."

Plain-language scope (per the excerpt). An originator sends a copy of an electronic message to a system, or composes it within the system. The system creates and records a digital signature of each message — e.g., by hash function producing a message digest, then encrypting the digest — with separate signatures possible for the body, attachments, and the overall message. The system forwards the message to recipients (including "to" and "cc" addressees) and returns a receipt containing the original message, the digital signature, and a handshaking and delivery history with delivery times. Later, the originator submits the receipt back to the system, which verifies that the signature matches the original message and the rest of the receipt; on a match, the system issues a letter or other confirmation of authenticity that the message has not been altered. The excerpt also characterizes the invention as a method including "receiving from a sender across a computer network an electronic message, the message having a delivery address associated therewith; computing a message digest according to the mes[sage]…" (truncated in the source).

Source: https://patents.google.com/patent/US7865557/en

What the excerpt does not establish. The supplied text is explicitly an excerpt with omitted material; the full claim set, claim numbering, dependencies, and the complete limitations of the appended claims are not reproduced here. It also omits the detailed description, drawing descriptions, and any specific embodiments. Accordingly, no statement of exact claim scope, claim count, or infringement position can be grounded in this text alone. Bibliographic fields and legal-status entries are as listed by the source and are labeled there as assumptions, not legal conclusions.