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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 0x492cd40bd52ef33f4f1539a87812b5596ef1647097333ded58663e87cbeb27f2. 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/c9ebf08e-e724-4742-99da-9c4611a6d767.json and https://artists.proofprofile.net/proofs/artist/c9ebf08e-e724-4742-99da-9c4611a6d767.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 0x2981bd3a18aff7a8b692dcb562b3245bb9796294e48e11ac7a914afe3519e58a. Chain 2 (Bitcoin): anchored in block 958373 (2026-07-17T06:09:33Z), 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/QZNJY2396009.
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0x2981bd3a18aff7a8b692dcb562b3245bb9796294e48e11ac7a914afe3519e58a. Chain 2 (Bitcoin): anchored in block 958224 (2026-07-16T02:28:43Z), 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/QZNJY2396009.
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0x367c410445e14bbdaba536d5d11e2021625e83999e1d8c8c88ffb033dd74f943. Chain 2 (Bitcoin): anchored in block 956474 (2026-07-03T08:56:35Z), 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/QZNJZ2388518.
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0x7de724424193eccc080768268fb15a35cdd587a67a83c779d1b9b75a752a7c1a. Chain 2 (Bitcoin): anchored in block 957833 (2026-07-13T09:36:32Z), 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/QZ5AB2407157.
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0x0c42f4e9343ffee70a7f57df5a236f887afc6b9b97de96804daef03ad7c0751f. 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/QZ5AB2407158.
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0xcf3a4f86224e04a64c6b1c49f40a4de670c75d2fe5eaa3ce7e24c41196478b0c. Chain 2 (Bitcoin): anchored in block 956578 (2026-07-04T02:23:20Z), 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/QZ5AB2407159.
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0xccbf2125345e8175a21f216aafd98ebfbe987a8383a2369ee24260380d489585. 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/QZGLM2445566.
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0xccbf2125345e8175a21f216aafd98ebfbe987a8383a2369ee24260380d489585. Chain 2 (Bitcoin): anchored in block 958373 (2026-07-17T06:09:33Z), 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/QZGLM2445566.
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0x481c6de25c7fcf8ffff9f87471bb499969d55983c9ff004c024f614ae9e2b0bf. Chain 2 (Bitcoin): anchored in block 956474 (2026-07-03T08:56:35Z), 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/QZNJY2410956.
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0xe6c25cd1a9368eaeee9829caa62b7d6832f49dbb5a5ed2cdb5e303c8ca7534a6. 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/QZTB82433941.
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0xea82f2b26b09c1c06ff436012e3aa111d166d1320ce2f35332c19bcb97b8b33f. Chain 2 (Bitcoin): anchored in block 958444 (2026-07-17T19:12:23Z), 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/QZMEN2595481.
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0xcfec4ef6627f4e3756229bbdeffba526e6fe06f9ae5a0f9b47b8c10f13d3d73a. Chain 2 (Bitcoin): anchored in block 959144 (2026-07-22T15:38:35Z), 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/QZTB22593763.
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0x70e0431cbdac000d3c414d8f923e5358235c3b2f415e6c93821b486e512fd862. Chain 2 (Bitcoin): anchored in block 958600 (2026-07-18T19:24:05Z), 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/QZTB22593764.
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0xea82f2b26b09c1c06ff436012e3aa111d166d1320ce2f35332c19bcb97b8b33f. Chain 2 (Bitcoin): anchored in block 958373 (2026-07-17T06:09:33Z), 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/QZMEN2595481.
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0x75408d411a46ee4320ab4ba4541a32f83cbc37d4aefadffa18285fae0ab9a685. Chain 2 (Bitcoin): anchored in block 958931 (2026-07-20T21:15:01Z), 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/QZTB22593767.