thumb|Nicolas Hotmann, 1650 Nicolas Hotman (also Autheman, Haultemant, Hautman, Otteman; ca. 1610–1663) was a Baroque composer, who spent most of his career in France. He is believed to have been from
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 0x29cde9b09b3ab412346a68eda251a8dc1d2ccc74f5adfdb657f3d43f9227b34c. Chain 2 (Bitcoin): anchored in block 953996 (2026-06-16T20:04:35Z). Bridge: the canonical record inside this Bitcoin proof contains the same CopyrightID. Verify: download https://artists.proofprofile.net/proofs/artist/2f5cbbf9-76ae-4c7f-8f24-d83b095521cb.json and https://artists.proofprofile.net/proofs/artist/2f5cbbf9-76ae-4c7f-8f24-d83b095521cb.ots, run `ots verify -f record.json proof.ots` (https://opentimestamps.org).
Manuscrit de Cracovie, Suite in D Minor: Ballet
La messagère: XVII-XXIe siècles, un portrait de la viole de gambe
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
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0x32ac5f45839f140cda9d472fa5641a0426cf7ddc62d2eac46445e7e638363356. 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/FR50X2407011.
Manuscrit de Cracovie, Suite in D Minor: Prélude du Sieur Dubuisson
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0x177deb2b4da44abec25060aa2d3e2d0db7f0b25f6b0dc64ab0581cd99b561c38. Chain 2 (Bitcoin): anchored in block 956312 (2026-07-02T05:09:12Z), 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/FR50X2407010.
Manuscrit de Cracovie, Suite in D Minor: Sarabande et sa variation
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0xa955812cc17a2f8db630b86d85807ed50a6e8ff1074bd79d2166ab62cb142d3a. Chain 2 (Bitcoin): anchored in block 956351 (2026-07-02T11:38:34Z), 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/FR50X2407013.
Manuscrit de Cracovie, Suite in D Minor: Courante et ses variations
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0x10bab32c97259ef448fbff5480d50e3094d3b3ab35af450b4c4d6fa4be5e7b0b. Chain 2 (Bitcoin): anchored in block 959155 (2026-07-22T19:24:43Z), 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/FR50X2407012.
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
Manuscrit de Cracovie, Suite in D Minor: Gigue et ses variations
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0x9b8bb86dfc8b68e79f3b826a06e1ae472cde717c7a749cb5bfd7f7b8aae07f6c. Chain 2 (Bitcoin): anchored in block 959163 (2026-07-22T20:34:51Z), 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/FR50X2407014.