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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 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 0xc23482c8e7005575609cacb13a0c38ce67dd3abec9120711039d075d03db99ff. Chain 2 (Bitcoin): anchored in block 954638 (2026-06-21T03:45:44Z). Bridge: the canonical record inside this Bitcoin proof contains the same CopyrightID. Verify: download https://artists.proofprofile.net/proofs/artist/d44de205-2337-4a36-a43d-0d3ccdb84dcb.json and https://artists.proofprofile.net/proofs/artist/d44de205-2337-4a36-a43d-0d3ccdb84dcb.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 0x5217ebf2d4fd0d0af7d09a646d0dd9c4790166ec98a9461532bc95ca39fb90c4. Chain 2 (Bitcoin): anchored in block 960354 (2026-07-31T05:48:18Z), 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/SEYP42212401.
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0x5e5bfc9281d8c62e98a99c30431a145182287cef88c720e0d222f6a864e2de4d. Chain 2 (Bitcoin): anchored in block 957120 (2026-07-08T03:22:41Z), 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/SEYP42212402.
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0x60476f0ba0ca508038bfdca6032779e27c4f3d9c6874d9b1a891b9949d287dd2. Chain 2 (Bitcoin): anchored in block 960370 (2026-07-31T08:38:45Z), 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/SEYP42212403.
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0x20e1a5054138710dde6f486feca33ac392a738fe1afbbbfd6ceefac60ec6d51a. 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/SEYP42212404.
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0xc7899477dc93fdd3b1dc5454d35b692299299d679a4e76fc839805b0327ae874. Chain 2 (Bitcoin): anchored in block 957120 (2026-07-08T03:22:41Z), 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/SEYP42212405.
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0x57907f1518368d740287bef723d70404534660a9b9fb84245658ea75bda51c4b. Chain 2 (Bitcoin): anchored in block 960258 (2026-07-30T12:45:34Z), 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/SEYP42212408.
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0x77b6a9662b4d4e4ed35d188ab645871a5cd80b550c93d42175727883ce0fb073. Chain 2 (Bitcoin): anchored in block 957120 (2026-07-08T03:22:41Z), 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/QZNWZ2068161.
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0x37dc6aeceeb7b266a636e62bc5091132b45ad358b267e406a3fe5274a7353234. Chain 2 (Bitcoin): anchored in block 957120 (2026-07-08T03:22:41Z), 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/QZNWZ2068162.
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0xdff7dfaee50b9632df022a9bd695ac48c62288dec22b30a1891bdcb4ba7db7ef. Chain 2 (Bitcoin): anchored in block 957120 (2026-07-08T03:22:41Z), 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/QZNWZ2068168.