CO-FONDATEUR · 01
Jérémy
Co-founder — Product & Cryptography
Jeremy designs the product experience and cryptographic architecture. OpenTimestamps, SHA-256 and eIDAS standards specialist.
INSTITUTIONAL NOTICEABOUT LEGALSTAMPEST. MMXXV
About LegalStamp.
We help creators, businesses, and legal professionals prove the priority of their documents in seconds using the Bitcoin blockchain.
§ I · MISSION
Our mission
LegalStamp makes legal timestamping simple, fast, and transparent. We use the OpenTimestamps protocol to anchor a cryptographic fingerprint of your files in the Bitcoin blockchain, without ever storing the document itself.
Our ambition is to democratize reliable proof of existence, complementary to traditional approaches (INPI, Soleau envelope), with a smooth user experience and a strong commitment to confidentiality.
§ II · GENÈSE
Our story
LegalStamp was born from a simple observation: proving you created a document before someone else used to be either slow (registered mail, INPI Soleau envelope), expensive (notary, qualified eIDAS trust services), or fragile (screenshot, email to yourself).
Founded in 2024 by a team of French cryptographers and lawyers, LegalStamp combines the cryptographic robustness of the Bitcoin blockchain with the simplicity of a web service. In seconds, you get a lifetime-verifiable proof of priority, without your file ever leaving your browser.
Today, more than 8,000 creators, freelancers, agencies, IT services firms and legal professionals use LegalStamp to protect source code, graphic works, contracts, drafts and ideas before publication or disclosure.
§ III · The team
The team
A multidisciplinary team combining cryptography, digital law and product UX.
CO-FONDATEUR · 02
Mehdi
Co-founder — Security & Platform
Mehdi leads security, platform and GDPR compliance. Background in applied cryptography and digital trust services.
§ IV · Standards and compliance
Standards and compliance
We rely exclusively on open standards and recognized legal references.
RÉFÉRENCE · 01
eIDAS Regulation
Simple electronic timestamping is defined in Article 41 of Regulation (EU) No 910/2014. LegalStamp produces a proof compatible with simple eIDAS timestamping.
RÉFÉRENCE · 02
OpenTimestamps
Open source protocol maintained by Peter Todd, based on Merkle trees and the Bitcoin blockchain. No private data is ever transmitted.
RÉFÉRENCE · 03
SHA-256
Standardized cryptographic hash algorithm (NIST FIPS 180-4). Computed locally in the browser, without uploading the original file.
RÉFÉRENCE · 04
2025 case law
In March 2025, the Marseille Judicial Court accepted the blockchain as proof of priority in copyright law. A milestone for legal recognition of blockchain evidence.
§ V · Our values
Our values
01
Transparency
We use the open source OpenTimestamps protocol. Every proof is independently verifiable, without depending on LegalStamp.
02
Privacy
Your files never leave your browser. We only collect the cryptographic fingerprint, making any content reconstruction impossible.
03
Accessibility
A free plan for everyone, clear pricing, and an interface designed to be usable without technical expertise.
§ VI · TECHNOLOGIE
Our technology
LegalStamp relies on the OpenTimestamps protocol and the Bitcoin blockchain. Your file's SHA-256 hash is computed locally, then anchored via a Merkle tree in a Bitcoin transaction. This architecture guarantees an immutable proof, verifiable by anyone, independent of any trusted third party.
§ VII
Legal credibility
In March 2025, the Marseille Judicial Court recognized the evidentiary value of a Bitcoin blockchain timestamp to establish the priority of a creation. This event confirms the relevance of proof based on OpenTimestamps.