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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 0xad8304cdb471b6555ecf9b896054675eb74d5cf647f992cb299cde243143ac56. Chain 2 (Bitcoin): anchored in block 953407 (2026-06-12T19:24:56Z). Bridge: the canonical record inside this Bitcoin proof contains the same CopyrightID. Verify: download https://artists.proofprofile.net/proofs/artist/8d24ea6d-ab36-420d-80a0-7e9acf5f06d7.json and https://artists.proofprofile.net/proofs/artist/8d24ea6d-ab36-420d-80a0-7e9acf5f06d7.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 0x51d5f0be99384158450234d7f373436d2a5c001331329cc5d82121afe790b8a4. Chain 2 (Bitcoin): anchored in block 958991 (2026-07-21T10:04:40Z), 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/DELJ81769673.
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0x65b9d56f6063373ec883597a2e9a912a3e2e9d08b5e6bc1b12e74799282948b5. Chain 2 (Bitcoin): anchored in block 958276 (2026-07-16T10:20:17Z), 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/NL1AP1901892.
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0x014ad8f0b4e578fa82a4b901a4668cee6197c4d3724a2229ff5f3fb127795cf8. Chain 2 (Bitcoin): anchored in block 958706 (2026-07-19T08:50:34Z), 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/NL1AP1901893.
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0xb03d2cbb16b06bca321370fa9a75bf398fdc36a53b03d6cdf906f7cf1655bb73. Chain 2 (Bitcoin): anchored in block 956476 (2026-07-03T09:04:44Z), 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/NL1AP1901894.
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0x052ea0b66566216655f74bf5478a452b89161436e3e2d3764b817bcc05576f58. Chain 2 (Bitcoin): anchored in block 956772 (2026-07-05T10:01:46Z), 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/NL1AP1901896.
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0x3bca221bb11121ddbb1a8d4b899591f3b444a5117c6acaef6dfce8f8aa6e8b4e. Chain 2 (Bitcoin): anchored in block 956375 (2026-07-02T16:51:38Z), 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/NL1AP1901901.
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0x04a3f90a727d12a0dc3c6341bbb6543c1c7a82961925c85a8f13e83a5954eb00. Chain 2 (Bitcoin): anchored in block 958897 (2026-07-20T14:57:46Z), 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/NL1AP1901903.
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0xd5130fd669f231f83562ef83872018107005de16e6c9c6fd1ef1f37554c70911. Chain 2 (Bitcoin): anchored in block 957805 (2026-07-13T04:34:37Z), 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/NL1AP1907364.
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0x9740663c9636c344f50b26d49572fc77c8e4b26aae8ac5ec61e6d2c3402e41ca. Chain 2 (Bitcoin): anchored in block 958621 (2026-07-18T22:59:44Z), 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/NL1AP1907365.
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0xd27beac2d9020b8dc7deda630759d229871c9b6494ac901ecb46d648388591f0. 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/NL1AP1907368.
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0xed1441c590e9f2dfd501c89d1102651da48a64f15869a8df6ee4234be0926bc7. Chain 2 (Bitcoin): anchored in block 958776 (2026-07-19T20:11:59Z), 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/NL1AP1907370.
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0xf25011232146e21b73614f0c31389d37caf963423f28806f0fb7bc95e32ffbfa. Chain 2 (Bitcoin): anchored in block 956545 (2026-07-03T19:59:51Z), 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/NL1AP1907371.
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0x64608abca72f69fc9b277559aeb40a7eace46d2143374e4bd190099828e1400c. Chain 2 (Bitcoin): anchored in block 958137 (2026-07-15T09:47:57Z), 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/NL1AP1990269.
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0x892fe09d03d58da762f962520517c562286673e8a841fa4dc29e49bbb16827f0. Chain 2 (Bitcoin): anchored in block 956634 (2026-07-04T10:04:33Z), 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/NL1AP1990271.
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0xadb4274a0a158865d035d41355a6d928ec32b964f43b3209de7ef8d4e4dbebe4. Chain 2 (Bitcoin): anchored in block 956772 (2026-07-05T10:01:46Z), 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/NL1AP1990272.
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0x656dea97274cefadd9569517db2166f0322a9f523a84f533b7983342108acffb. Chain 2 (Bitcoin): anchored in block 957888 (2026-07-13T17:43:59Z), 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/NL1AP1990273.
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0x63c20b19389bc3a3cd8b748f0d4c67d0541100988d83726e31ed4c7dee0b1598. Chain 2 (Bitcoin): anchored in block 958428 (2026-07-17T15:15:14Z), 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/NL1AP1990274.
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0x9c6d7e27428bea76dadab5764844480eafa9265423432c71b22804ed50597a3d. Chain 2 (Bitcoin): anchored in block 956375 (2026-07-02T16:51:38Z), 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/NL1AP1990276.