Sonnerie is French for "making sound" or "ring". The term generally applies to bell towers or bells in mechanical clocks or wristwatches (see for example grande sonnerie), but can equally be used, fo
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
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0xf8ce2f3c8d24ab6af5a19edf6d6f174915bb2bcd38d2ab7b037c7765383db8f5. Chain 2 (Bitcoin): anchored in block 954623 (2026-06-20T23:40:06Z). Bridge: the canonical record inside this Bitcoin proof contains the same CopyrightID. Verify: download https://artists.proofprofile.net/proofs/artist/cb533b17-063d-40ae-b4fa-82848f22367e.json and https://artists.proofprofile.net/proofs/artist/cb533b17-063d-40ae-b4fa-82848f22367e.ots, run `ots verify -f record.json proof.ots` (https://opentimestamps.org).