thumb|270px|Inside the cathedral of Sens, Jean-Baptiste-Camille Corot, Sens () is a commune in the Yonne department in Bourgogne-Franche-Comté in north-central France, 120 km southeast from Paris.
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 0x7ca7b00035b4f770ca95f09f85cdb0dcca5607667d664b22d25e0ed96c9ce293. Chain 2 (Bitcoin): anchored in block 953742 (2026-06-15T04:47:56Z). Bridge: the canonical record inside this Bitcoin proof contains the same CopyrightID. Verify: download https://artists.proofprofile.net/proofs/artist/86ecef0a-5dcb-42ef-a340-a37a272ca01d.json and https://artists.proofprofile.net/proofs/artist/86ecef0a-5dcb-42ef-a340-a37a272ca01d.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
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0x504ad72536abe909e7eddd722a2a788c67148167284f126c8d550d4a4095087e. Chain 2 (Bitcoin): anchored in block 956790 (2026-07-05T12:31:54Z), 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/QZFYW1961892.
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0xfe0d86e97fc096b1b81a28d255877f7f9625e19ff2fe4ee6cbae1858ca5127ff. Chain 2 (Bitcoin): anchored in block 956639 (2026-07-04T11:19:20Z), 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/QZFYW1961894.
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0x931e5b32ff71bfe69cad7391baa4518de4fdc8decf89a45defaae305adf8ab05. 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/QZMER2010933.
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0xff79ffae4f907f185644a0b5744f27c4225f07392c6f0f38f949bb7ae4a05491. Chain 2 (Bitcoin): anchored in block 958180 (2026-07-15T20:33:30Z), 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/QZMER2010934.
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0x3358f60ae69516e6aa29c1055e3c317d5a10957bcf373dfb067da1a02bd168f4. Chain 2 (Bitcoin): anchored in block 957961 (2026-07-14T05:58:47Z), 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/QZMER2010935.