Proven solutions using cryptography and blockchain


TraaaX by KeeeX is a combination of 4 solutions

Enriching a document, locking its integrity, guaranteeing its authenticity, tracing its history, verifying that it’s the latest version or transferring ownership of an original is easy with TraaaX. Our tool makes it easy to handle simple cases as well as the most complex processes.

KeeeX Fusion

Self-proving files (integrity, signature(s), date, anchoring in the blockchain, contextual metadata, etc.).

KeeeX Stories

Auditable sequential registers in file mode for tracing the history of a reference (document, product, process, etc.)

KeeeX Chain

A private blockchain open to reading and publicly auditable to trace variable properties (owner, version, support, etc.).

KeeeX Anchoring

A public blockchain to record proof of existence of files and system states at regular intervals (bi-daily shared anchorage)

The 3 main elements of the Transferable Electronic Records

They are necessary to prove possession and ensure the transfer of a document related to international trade.


Any format, can be enriched, signed, timestamped, endorsed, owned, verified.


A cryptographic key pair to sign files, prove ownership or initiate a transfer.

Ledger / Blockchain

A hybrid private and public blockchain system to track everything and make it verifiable

KeeeX technology

We combine the best of cryptography and blockchains to enable you to dematerialize and trace your files with ease.

KeeeX patented technology

Our unique technology enables any file or document to self-carry evidence of its integrity via a multihash called IDX, its provenance via one or more digital signatures, a legal timestamp and proof of existence on one or more blockchains, without altering its visible content or exploitation.

Equipped in this way, a file is protected for an unlimited period of time, and can be verified without the need for a trusted third party. It can be stored and archived without recourse to a specific infrastructure, and preserves its evidential value even on a USB key or in an e-mail.

Energy – KeeeX fully offsets its emissions

First and foremost, KeeeX has been using the Bitcoin blockchain in “Layer 2” since 2014 as the ultimate source of proof through mutualized twice-daily writings. The CO2 emissions resulting from this activity remain moderate (150T eCO2) and are included in the offsetting of all KeeeX emissions (165T eCO2) declared to Ademe since 2022 (including those from our servers and the KeeeX Chain blockchain).

Unique file identifier – self-supporting IDX

KeeeX attaches to each keeexed document a unique, tamper-proof, humanized identifier that can be used by users or in other documents to reference it. This identifier, injected into the file, is called its IDX – for example:


Since KeeeX Fusion version 2, this IDX has been calculated using an innovative multi-hash algorithm designed to multiply its durability (bearing in mind that cryptographic fingerprints are quantum-resistant anyway).


A keeexed file usually bears a combination of signatures of its issuer and the issuing company, making the document impossible to forge in the current state of technology, even by an engineer with control of the systems. These signatures play a considerable role in preventing the creation of forgeries, both in the transferable file itself and in the transactions issued on the register to materialize transfers of ownership and declarations of new versions.


These properties are complemented by a blockchain infrastructure combining :

  • mutualized twice-daily anchor certificates on the Bitcoin blockchain as a source of “perpetual” audit trails for keeexed documents. These are in Bitcoin layer 2. KeeeX allows the anchor proofs themselves to be injected into the files (using Merkle branches), making the files completely autonomous, including access to the blockchain proofs of existence.
  • a blockchain with public observer and explorer nodes ( for high-speed execution of smart contracts without gas costs. This blockchain is also in layer 2 of Bitcoin.
  • auditable historical registers in file mode that compensate for the weakness of blockchains in this area and provide access to documents (file versions). These registers can be used to create auditable proof records in the form of files (easily retrieved as a zip archive) attesting to the reality and sequentiality of a process, for data that should not or cannot be recorded in blockchain. Indeed, smart contracts, whether operated on public or private blockchains, are highly unsuited to historization.
  • Smart contracts dedicated to recording variable properties(“owner”, “most recent version”, “transfer to paper completed”, “expiry status” …) designated in the files themselves. Ideally, these smart contracts should be operated on a publicly auditable blockchain.
  • Zero knowledge proofs injected into the files enable only selected components to be revealed, without losing the strength of the proof.

This approach thus combines the perpetual static verifiability provided by files, the real-time protection provided by the KeeeX Chain blockchain, the auditable historization enabled by KeeeX Stories, the permanent securing of all valid states by Bitcoin and the intangible association of a tamper-proof document with its variable properties.

In the context of MLETR, KeeeX enables the tamper-proof association of a cryptographically certified file and the recording in one or more registers (blockchain or not) of variable properties of this file, including the Titularity (who owns?) of the document. In this context :

  • the information describing the register that must be queried to find out the value of a variable property is recorded in the document and made tamper-proof by KeeeX proofs.
  • the property registration key used in the registry (typically a smart contract on the KeeeX Chain blockchain but possibly others) is precisely the file’s unique, tamper-proof fingerprint (IDX).

These elements enable the certain tamper-proof bi-directional association between the registry and the file, and thus the verifiable and auditable change of ownership without time limit or third party of an electronically transferable title, which lifts a considerable technological lock to the implementation of MLETR.

These functionalities and services are protected by several granted CNRS patents (FR/US/EU) or a more recently registered KeeeX patent.

Start your digital journey With KeeeX


37 rue Guibal