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 0xf6273e12763eca698f22a8b9c0f218a4d13e8296e8d9cbfaad45483eb883b86f. Chain 2 (Bitcoin): anchored in block 954139 (2026-06-17T21:12:18Z). Bridge: the canonical record inside this Bitcoin proof contains the same CopyrightID. Verify: download https://artists.proofprofile.net/proofs/artist/803016f6-2eec-4653-9bb3-0b26a16d3cd1.json and https://artists.proofprofile.net/proofs/artist/803016f6-2eec-4653-9bb3-0b26a16d3cd1.ots, run `ots verify -f record.json proof.ots` (https://opentimestamps.org).
Sonata in D Minor, Kk. 89: I. Allegro (Transcr. for Mandolin and Basso continuo)
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 0xdeddad17d66745ce3ecb35cb14e5af9fe6cf5261188761a561d7655a3cd83d80. 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/DEN962000601.
Sonata in D Minor, Kk. 89: II. Grave (Transcr. for Mandolin and Basso continuo)
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0xc2215f0f6d5d71d90b2055645ef40a6a76837a85d61c79c305a52e417b4b1851. Chain 2 (Bitcoin): anchored in block 956302 (2026-07-02T03:30:09Z), 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/DEN962000602.
Sonata in D Minor, Kk. 89: III. Allegro (Transcr. for Mandolin and Basso continuo)
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0x1e87d2026ecc260ca483fd4fd4c4b2ddc78c605174ed4c72c16f66439a0ebaa8. Chain 2 (Bitcoin): anchored in block 960264 (2026-07-30T14:36:16Z), 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/DEN962000603.