US Patent 7596689 Secure and reliable document delivery using routing lists

An operations center (OC) (200) acts as an intermediary for securely and reliably transmitting a document (3) from a sender (100) to a next recipient (300) on a routing list. The OC (200) identifies (464) a recipient (300) from the next stage of the routing list and provides either the recipient's public key (404) or an escrow encryption key (406). The OC (200) optionally can authenticate the sender (100) and/or the recipient (300), thus increasing security.