A smart contract is a self-executing computer program deployed on a blockchain that automatically triggers actions when predefined conditions are met. For example: "if payment is received, then transfer ownership of the asset". This if/then logic removes the need for an intermediary to enforce the contract.
The most widely used programming language for smart contracts is Solidity, deployed on the Ethereum blockchain. Under French law, smart contracts are governed by the Civil Code: Article 1103 (binding force of contracts), Article 1127-1 (electronic contracts) and Article 1366 (electronic writing). In February 2025, UNCITRAL adopted a model law on smart contracts, paving the way for international harmonisation.
The legal applications are numerous: automatic execution of warranty clauses, management of intellectual property rights, automated escrow, and contractual penalty clauses. However, the immutability of the code raises questions around the amendment and judicial termination of contracts, which calls for hybrid drafting that combines code with traditional legal clauses.