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 0x713ea545ddd3b6eecc919fb681ee459ebd5f319189e9447f9649f1a08958339e. Chain 2 (Bitcoin): anchored in block 954062 (2026-06-17T07:39:10Z). Bridge: the canonical record inside this Bitcoin proof contains the same CopyrightID. Verify: download https://artists.proofprofile.net/proofs/artist/4729fb42-24cd-4bd7-9545-d3dd278f819a.json and https://artists.proofprofile.net/proofs/artist/4729fb42-24cd-4bd7-9545-d3dd278f819a.ots, run `ots verify -f record.json proof.ots` (https://opentimestamps.org).
Schubert: String Quartet No. 14 "Death and the Maiden" & Sibelius: String Quartet "Intimate Voices"
String Quartet No.14 in D Minor, ‘Death and the Maiden’ D. 810: I. Allegro
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 0xc15c8b2d0af9832c936b9cab402d743a4a7450ee810503c9ed842ad4baa0d69f. Chain 2 (Bitcoin): anchored in block 960111 (2026-07-29T13:21:01Z), 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/GBPCP1600232.
String Quartet No.14 in D Minor, ‘Death and the Maiden’ D. 810: II. Andante con moto
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0xc20cc57aa187f56197d51e47167c5ac8361cd2ad2733d6d3df98ef7c895bf5a3. Chain 2 (Bitcoin): anchored in block 960225 (2026-07-30T08:04:30Z), 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/GBPCP1600233.
String Quartet No.14 in D Minor, ‘Death and the Maiden’ D. 810: III. Scherzo - Allegro molto
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0x37f6cdc64ed83b9c0bc14134d1941b19b378050df9a9859a43e466f902261692. 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/GBPCP1600234.
String Quartet No.14 in D Minor, ‘Death and the Maiden’ D. 810: IV. Presto – Prestissimo
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0xae5f63d015671a8283d0cbf1d9b3db95488f4a95bfed86b84160e09ae5e05c8a. 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/GBPCP1600235.
String Quartet in D Minor, ‘Intimate Voices’ Op. 56: I. Andante – Allegro molto moderato
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0xf04983fbe6f9b827cc83eab39b61c9dc1faaedbecb19a1a1b37fea54ecbb0f30. Chain 2 (Bitcoin): anchored in block 960427 (2026-07-31T15:59:18Z), 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/GBPCP1600236.
String Quartet in D Minor, ‘Intimate Voices’ Op. 56: III. Adagio di molto
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0xfcb2572fa5bdcf8004765b4acddc475a51f147bbd0d3a37cd3983669350a9a77. Chain 2 (Bitcoin): anchored in block 960268 (2026-07-30T14:53:07Z), 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/GBPCP1600238.
String Quartet in B Minor, Op. 11: II. Molto adagio -
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0xad7dba10926eb49810fbddc9310f95c8f413e9bf43b48b7fa6debcea3b1b2c96. Chain 2 (Bitcoin): anchored in block 960403 (2026-07-31T13:04:34Z), 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/GBPCP1400068.