A Formal Treatment of Contract Signature

The paper develops a logical understanding of processes for signature legal contracts, motivated by applications to recognition smart contracts on blockchain platforms. A number axioms and rules inference are developed that can be used justify ``meeting the minds'' precondition contract formation from fact certain content has been signed. In addition an ``offer acceptance'' process, considers ``signature in counterparts'', process permits between two or more parties brought into force having independently (possibly, remotely) sign different copies contract, rather than placing their signatures common copy at physical meeting. It is argued satisfactory account counterparts benefits logic with syntactic self-reference. supported formal semantics, further properties investigated. particular, it shown implies when signed, do not just agree, but mutual agreement (a common-knowledge-like notion) about terms contract.