A blockchain lawyer provides legal certainty for projects built on distributed ledger technology: smart contracts, asset tokenisation, timestamping, protocol governance. In Paris, Hashtag Avocats assists founders, companies and investors building on blockchain. This page deals with the technology and its uses; the regulation of crypto-assets (MiCA, tax) is covered in detail on our crypto-asset lawyer page.
The law applicable to blockchain in France
There is no “blockchain code”: French law has recognised the technology step by step. Ordinance No. 2017-1674 of 8 December 2017 allowed financial securities to be recorded in a shared electronic recording device (DEEP, dispositif d’enregistrement électronique partagé), in other words a blockchain. Law No. 2019-486 of 22 May 2019, known as the PACTE Act, then set the framework for digital assets and token offerings. Since then, Regulation (EU) 2023/1114 (MiCA) has governed crypto-assets, and Ordinance No. 2024-936 of 15 October 2024 replaced the DEEP with the concept of “distributed ledger technology”. Otherwise, general law applies: contracts, evidence, intellectual property, personal data. The lawyer’s job is to classify each building block of the project in order to identify the applicable regime.
Smart contracts: what legal value do they have?
A smart contract is a program that automatically executes instructions when predefined conditions are met. It is not, in itself, a contract within the meaning of the French Civil Code (Code civil): it can be the automated performance of one. The legal contract remains the agreement between the parties that surrounds it. Hence three precautions: back the code with clear contractual documentation (which prevails in the event of a discrepancy), provide for how execution errors and failing oracles are handled, and set out the governing law and the competent court. We audit the consistency between the deployed code and the written commitments.
Asset tokenisation and financial securities on DLT
Tokenisation means representing an asset (a financial security, a fund unit, a real-world asset) by a token recorded on a blockchain. The legal classification of the token determines the entire applicable regime.
Recording financial securities using distributed ledger technology (formerly DEEP)
Since the 2017 ordinance, financial securities that are not admitted to the operations of a central securities depository may, by decision of the issuer, be recorded using distributed ledger technology (Articles L211-3 and L211-7 of the French Monetary and Financial Code (Code monétaire et financier) (in French)). This recording takes the place of a book entry. A company can therefore keep its securities register on a blockchain, with authentication safeguards at least equivalent to those of a book entry in a securities account. This is the historical French route to tokenising securities.
The EU DLT pilot regime
Regulation (EU) 2022/858, applicable since 23 March 2023, opens a pilot regime for market infrastructures based on DLT. Subject to a specific permission, it allows the operation of trading venues (DLT MTF), settlement systems (DLT SS) or combined structures (DLT TSS) for tokenised financial instruments. This regime is of interest to projects that want tokenised securities to circulate on a market scale.
Blockchain and evidence: timestamping, traceability
Recording a hash on a public blockchain provides a timestamp that is difficult to falsify: it shows that a piece of content existed on a given date. Under French law, legal facts may be proved by any means: a blockchain anchor can therefore be produced in court, with its probative value left to the judge’s assessment. The practical uses are many: prior existence of a creation, integrity of a document, traceability of a supply chain. We help structure these systems so that they withstand challenge: quality of the hash, link to the original, anchoring reports.
Blockchain, GDPR and personal data
The immutability of blockchain clashes head-on with the GDPR rights to rectification and erasure. In its analysis dedicated to blockchain, the CNIL (French data protection authority) recommends never recording personal data in clear text in the ledger and favouring cryptographic methods (hashes, commitments), with the data themselves stored off-chain. It points out that the GDPR analytical framework applies in full: identifying the controller, exercise of rights, security, and prior consideration of whether the technology is relevant at all (privacy by design). The data architecture must therefore be designed with the lawyer from the moment the protocol is conceived.
Structuring a blockchain project: contracts, governance, intellectual property
Beyond compliance, a blockchain project is structured like a decentralised software project. Three workstreams: contracts (protocol development, security audits, partnerships, terms of use of the interfaces); governance, especially for decentralised autonomous organisations (DAOs), whose lack of a legal structure exposes their members: choosing a suitable vehicle (association, company) puts the treasury and liabilities on a secure footing; and finally intellectual property: protocol code that is often open source, trade marks, databases, know-how. These questions overlap with those of the Web3 (in French) projects we advise on.
Crypto-assets, ICOs, NFTs: our dedicated pages
Is your question about the assets rather than the technology? Three of the firm’s pages deal with it in detail: the regulation and tax treatment of crypto-assets (authorisations, MiCA, disputes), fundraising through token issuance on our ICO (in French) page, and non-fungible tokens on our NFTs and copyright page.
FAQ
Is a smart contract a contract in the legal sense?
No, not on its own. It is a self-executing program. The contract, within the meaning of the Civil Code, is the agreement between the parties that it implements. Good practice is to document that agreement in writing and to provide that the document prevails if it diverges from the code.
Is blockchain compatible with the GDPR?
Yes, provided the architecture is suitable. The CNIL recommends recording only cryptographic hashes on the chain, never personal data in clear text, and keeping the data off-chain where rights can be exercised. The very choice of blockchain must be justified under data protection by design.
What is asset tokenisation?
It is the representation of an asset by a token recorded on a blockchain, which allows it to be held and transferred. For financial securities that are not admitted to the operations of a central securities depository, French law allows recording using distributed ledger technology (Articles L211-3 and L211-7 of the Monetary and Financial Code). The classification of the token determines the applicable regime: financial security, crypto-asset subject to the MiCA Regulation, or a mere contractual right.
Which law governs blockchain in France?
No single law. The key texts are the ordinance of 8 December 2017 on the DEEP, the PACTE Act of 22 May 2019 for digital assets, the 2022 EU pilot regime for DLT market infrastructures and Regulation (EU) 2023/1114 (MiCA) for crypto-assets. General law (contracts, evidence, GDPR, intellectual property) applies to everything else.
Official sources
- Ordinance No. 2017-1674 of 8 December 2017 on the use of a shared electronic recording device for the representation and transfer of financial securities: Légifrance (in French)
- Article L211-3 of the French Monetary and Financial Code (Code monétaire et financier), recording of financial securities using distributed ledger technology: Légifrance (in French)
- Law No. 2019-486 of 22 May 2019 on business growth and transformation (PACTE): Légifrance (in French)
- Regulation (EU) 2022/858 on a pilot regime for market infrastructures based on distributed ledger technology: AMF (French financial markets authority) topic page
- CNIL, “Blockchain and the GDPR: what solutions for responsible use in the presence of personal data?”: cnil.fr (in French)
Law as in force on 6 July 2026. This content provides general information and does not constitute legal advice. Every situation is different: contact our team to have your blockchain project reviewed.
Our related digital law practice areas
- ICO lawyer: MiCA compliance & AMF approval (in French)
- Fake charity fundraising scam lawyer (in French)
- Bitcoin lawyer in Paris (in French)
- Investment scam lawyer: remedies and defence (in French)
- SaaS lawyer
Further reading
- Data security on the blockchain: definition (in French)
- Blockchain as a service: definition (in French)
- TAX REGULATION OF BLOCKCHAIN (in French)
- The IMF and the World Bank explore the merits of cryptography in a blockchain project (in French)