thumb|right|Cordier's rondeau about love, Belle, Bonne, Sage, is in a heart shape, with red notes indicating rhythmic alterations. Baude Cordier () was a French composer in the style of late medieva
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 0xab6354a9f39b3d2b7a5dee6b42a472e857a63c9dae68b8511d84feea7e504f77. Chain 2 (Bitcoin): anchored in block 953625 (2026-06-14T11:37:06Z). Bridge: the canonical record inside this Bitcoin proof contains the same CopyrightID. Verify: download https://artists.proofprofile.net/proofs/artist/27bcc47a-f647-4458-914e-78be6aa4e94a.json and https://artists.proofprofile.net/proofs/artist/27bcc47a-f647-4458-914e-78be6aa4e94a.ots, run `ots verify -f record.json proof.ots` (https://opentimestamps.org).
Baude Cordier: Complete Works (Arr. for Guitar)
Je voy le bon tens venir: Polyphonies & danses autour de 1400
1. Confirm isrcCode identifies the recording in the pre-2022 source corpus and cc-db-prod record 2. GET OTSVerificationAPI → server-side canonical-record, hash, and attestation checks must pass 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. Confirm CopyrightID is the CopyrightChains transaction hash 5. If all match: the cc-db-prod record is independently anchored on Bitcoin at OTSTimestamp 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 0x2a4fd725913c9a492620d041bc55eb51ca0a139698cc54ed820231bfeaf8adc8. Chain 2 (Bitcoin): anchored in block 960397 (2026-07-31T12:24:41Z), registered by our registry partner. The server verifies the private canonical record against OTSHash without exposing internal provider keys. Confirm the public ISRC, CopyrightID, and Bitcoin evidence via https://artists.proofprofile.net/api/v1/bot/ots/verify/track/FR50X1118902.
Tout par compas, Fol. 12 (Rondeau/Canon)
Codex Chantilly III - Bibliothèque du Château de Chantilly, Ms. 564
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0xffa5794aefb66b377a73790c8f18539cacc5b25bfce6b3e5e6c2b18a0f27d1e4. Chain 2 (Bitcoin): anchored in block 953520 (2026-06-13T13:32:09Z), registered by our registry partner. The server verifies the private canonical record against OTSHash without exposing internal provider keys. Confirm the public ISRC, CopyrightID, and Bitcoin evidence via https://artists.proofprofile.net/api/v1/bot/ots/verify/track/NLQ661491700.
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0x59f449363b13caeef2a5cf698fee55856d37a96aeae97781d651e74d409dd0cf. Chain 2 (Bitcoin): anchored in block 957118 (2026-07-08T03:20:19Z), registered by our registry partner. The server verifies the private canonical record against OTSHash without exposing internal provider keys. Confirm the public ISRC, CopyrightID, and Bitcoin evidence via https://artists.proofprofile.net/api/v1/bot/ots/verify/track/NLQ661491701.
Figures of Harmony: Songs of Codex Chantilly c. 1390
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0xa9d123eb26562b70e615dd263f48ffb5c23bc109872b74b132bf96133d293426. Chain 2 (Bitcoin): anchored in block 953515 (2026-06-13T12:53:06Z), registered by our registry partner. The server verifies the private canonical record against OTSHash without exposing internal provider keys. Confirm the public ISRC, CopyrightID, and Bitcoin evidence via https://artists.proofprofile.net/api/v1/bot/ots/verify/track/FR46Y9438203.