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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 0xedd53d574517c6ca531d91119a06664e1643c164fbea69c0aa0284094b4f2d74. Chain 2 (Bitcoin): anchored in block 953408 (2026-06-12T19:28:13Z). Bridge: the canonical record inside this Bitcoin proof contains the same CopyrightID. Verify: download https://artists.proofprofile.net/proofs/artist/8cdc1872-9fd9-47e0-8962-d9347600bf9c.json and https://artists.proofprofile.net/proofs/artist/8cdc1872-9fd9-47e0-8962-d9347600bf9c.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 0xc3fd5942a323717059e9ed45e91fcf6bb9db5c7c099e34177a6f623139dc85ef. 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/USE830935779.
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0xe24ac8adf1f4bc0ceb1650bd546f65412c0286923ae57a8fcfcebc1063bf0a5c. 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/USE830935780.
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0xdc03d53122a430f06ba1f7bf1aafa7b00020d48ef47c45065260dd3d37f8e61e. Chain 2 (Bitcoin): anchored in block 956856 (2026-07-06T01:25:57Z), 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/USMBR1108141.
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0x4d9ca5a4c459e2d0a9692ae569930e86d425d8f3ff2ad8b634270d9292ba5112. Chain 2 (Bitcoin): anchored in block 958404 (2026-07-17T11:34:58Z), 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/USMBR1108142.
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0x472043d51efcb10340817b5fb0050fd57e99b0761b5601aad1adc9a246fc8040. Chain 2 (Bitcoin): anchored in block 956738 (2026-07-05T04:47:21Z), 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/USMBR1108144.
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0x5cfaba9b8212207bab1295c1ddb261cb060a335a5b3bc2f7a0d9d84d73ed71c0. Chain 2 (Bitcoin): anchored in block 958484 (2026-07-18T03:34:53Z), 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/USMBR1108147.
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0xe32e14d5a701c51ef609207795c3c1ef1b71b7a719bcfc1f18574114b9dbb36d. Chain 2 (Bitcoin): anchored in block 958346 (2026-07-17T03:59:26Z), 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/USMBR1612032.
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0x3c85247c1c7ea460ffa2eb0548cd36b8d3ad5b62624df8c50d94400a283e3239. Chain 2 (Bitcoin): anchored in block 956826 (2026-07-05T19:27:56Z), 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/USMBR1612035.
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0x9fcd5e935173c30409a310053bd54d29b1e037fce018fbdbc326ca394f599d6d. Chain 2 (Bitcoin): anchored in block 956826 (2026-07-05T19:27:56Z), 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/SE6HB2000601.
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0x4cb85adada42a7f733528d623852a5720cdd1192d76a0d62eac581c270c13dcb. Chain 2 (Bitcoin): anchored in block 958074 (2026-07-14T22:45:25Z), 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/SE6HB2000702.
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0x23730d4a0179ae4fc2485dad450e907933b56d43bc6e910afb9da80e621238e0. Chain 2 (Bitcoin): anchored in block 956402 (2026-07-17T03:37:23Z), 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/SE6HB2000705.