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 0x5a05f20acfb862f001d42b4ef1daa210c0d955e60589a49dcff2e292ea8308ca. Chain 2 (Bitcoin): anchored in block 954549 (2026-06-20T10:56:20Z). Bridge: the canonical record inside this Bitcoin proof contains the same CopyrightID. Verify: download https://artists.proofprofile.net/proofs/artist/aaf69270-a0fa-4803-9564-6632dbfd8e5d.json and https://artists.proofprofile.net/proofs/artist/aaf69270-a0fa-4803-9564-6632dbfd8e5d.ots, run `ots verify -f record.json proof.ots` (https://opentimestamps.org).
Ottavo libro de' madrigali (Madrigali guerrieri, et amorosi ...), Venice, 1638 -Dolcissimo uscignolo, 'cantato à voce piena, alla francese' (sv161)
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 0xffe1c3f7bb4b506f8df28a7472c753aa685faebf3b5b50697ff2d17d2589a7b0. Chain 2 (Bitcoin): anchored in block 956304 (2026-07-02T03:55:08Z), 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/USX760801410.
Ottavo libro de' madrigali (Madrigali guerrieri, et amorosi ...), Venice, 1638 -Chi vole aver felice e lieto il core, 'cantato à voce piena, alla francese' (sv162)
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0x59350effd464da5475d758514ce93058cb190433698b0886539162bb84a993b9. Chain 2 (Bitcoin): anchored in block 960125 (2026-07-29T15:38:18Z), 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/USX760801411.