thumb|right|Giovanni Baglione. Divine Love Conquering Earthly Love (1602–1603), showing dramatic compositional chiaroscuro. In art, chiaroscuro ( , ; ) is the use of strong contrasts between light an
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 0x3b2363d368ab6c39892a158bf44d81f203f1339533c425c303dd8b12b46539d1. Chain 2 (Bitcoin): anchored in block 953786 (2026-06-15T12:56:12Z). Bridge: the canonical record inside this Bitcoin proof contains the same CopyrightID. Verify: download https://artists.proofprofile.net/proofs/artist/d8a6eab0-26e2-4bd3-81bf-f6c0950ae5e6.json and https://artists.proofprofile.net/proofs/artist/d8a6eab0-26e2-4bd3-81bf-f6c0950ae5e6.ots, run `ots verify -f record.json proof.ots` (https://opentimestamps.org).
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 0x18ba9fcdb0cbafe51fb21fbeef3c79f4c3867ab16c09565d256644e75093b343. Chain 2 (Bitcoin): anchored in block 958234 (2026-07-16T03:46:09Z), 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/IT2J82400005.
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0xce44a3fb70dbc7a1a4e68a5bef09d9c2f277e7a577f9f9a37626f21e6b1953ef. Chain 2 (Bitcoin): anchored in block 957891 (2026-07-13T18:21:04Z), 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/IT2J82400006.
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0xe87379b8e9a6533d8db1b0b822a2b7e27182a4305e6c55d47895d562a20fa0a6. Chain 2 (Bitcoin): anchored in block 958300 (2026-07-16T16:14:30Z), 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/IT2J82400007.
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0x40b121830247855c0d88fcf0593b58412e2cc5f9c43dd6d3a1730b4111c96e47. Chain 2 (Bitcoin): anchored in block 956422 (2026-07-03T01:01:38Z), 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/TCAHL2326026.
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0x9a8ea85dcd356df197955143aa5aeafbb129093e8672db8c187edc2c07f65227. Chain 2 (Bitcoin): anchored in block 956725 (2026-07-05T01:12:41Z), 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/IT2J82400008.