Check the versions of Duely’s list

The chain proves that the versions have not been rewritten since the hash you hold. The date comes from anchoring: each night the log has changed, the hash of its last line is sent to the public OpenTimestamps calendars, which write it into a Bitcoin block within a few hours; the proof then shows that this line, and all the lines before it, existed no later than the date of the block. It is not a qualified time stamp within the meaning of the eIDAS regulation.

Files of each deposit

• 1 November 2026, lines 1 to 1, confirmed in the Bitcoin blockchain (block no. 974076 of 1 November 2026, 04:58 Paris time) : Anchored text, .ots proof, RFC 3161 token (FreeTSA, 1 November 2026, 05:00 Paris time).

1. Download the full log (JSON).
2. The first line starts from the origin: SHA-256 of the text “registre-sous-traitants/registre/service”.
3. For each line, SHA-256(previous_hash + content), in hexadecimal, must give back its hash; the previous hash of a line is the hash of the line before. Lines that record notices to customers publish only their hashes (their content names the publisher’s customers): the chain stays continuous.
4. The content of each “version” line holds the list of that version, to compare with the page.
5. For the date: download the anchored text and its proof (.ots) above, then drop them together on the “Stamp & Verify” page of opentimestamps.org, which tells in which Bitcoin block the proof is, without installing anything. Another way: “ots verify” from the OpenTimestamps client, which needs a Bitcoin node on your machine.
6. For the date, without waiting for Bitcoin: the RFC 3161 token is signed the same day by FreeTSA. With OpenSSL: openssl ts -verify -data <anchored text> -in <.tst token> -token_in -CAfile cacert.pem -untrusted tsa.crt, the two certificates being the authority’s (cacert.pem, tsa.crt); “Verification: OK” confirms the text and the time.