An apparatus, system and method for establishing a transaction between first and second parties including a first signing step in which a transaction message including a request and a transaction identifier is cryptographically signed by the first party to form a first cryptographically signed message. The first signed message is transmitted from the first party to the second party. The second party then cryptographically signs the first message to form a second cryptographically signed message. The second message is also transmitted from one or more of a plurality of parties having the second message to a trusted third party. The trusted third party is able to verify that the second message was cryptographically signed by the second party and can also verify that the first message in the second message was cryptographically signed by the first party.