Caen (; ; ) is a city and commune inland from the northwestern coast of France. It is the prefecture of the department of Calvados. The city proper has 105,512 inhabitants (), while its functional ur
1. Compute SHA-256 of OTSCanonicalRecord value → must equal OTSHash 2. Open OTSProofURL → extract Bitcoin block number → must equal OTSBitcoinBlock 3. GET OTSBitcoinBlockVerifyURL → returns the Bitcoin block hash at height OTSBitcoinBlock; GET https://blockstream.info/api/block/{that hash} → its timestamp must match OTSTimestamp 4. Read CopyrightID inside OTSCanonicalRecord → must equal the CopyrightID above 5. GET OTSVerificationAPI → pre-computed 6-check result from server 6. If all match: this entity was registered on CopyrightChains at OTSTimestamp, independently verifiable on Bitcoin Note: an OTS proof may carry multiple Bitcoin attestations; OTSBitcoinBlock is the earliest confirmed one — a later attestation inside the proof corroborates it and is not a mismatch
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0xbbd0ad0f5369f35f4d04401ea053cfe5961f373d684a9e3614b04c110df11998. Chain 2 (Bitcoin): anchored in block 954587 (2026-06-20T19:10:41Z). Bridge: the canonical record inside this Bitcoin proof contains the same CopyrightID. Verify: download https://artists.proofprofile.net/proofs/artist/b8919f5a-efbc-4c17-84b1-b5238741d313.json and https://artists.proofprofile.net/proofs/artist/b8919f5a-efbc-4c17-84b1-b5238741d313.ots, run `ots verify -f record.json proof.ots` (https://opentimestamps.org).