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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 0xeabb9fc7d3e852b5084d9294390bed8d08f3d492989b81f9b9d239e60b242de3. Chain 2 (Bitcoin): anchored in block 953648 (2026-06-14T15:20:52Z). Bridge: the canonical record inside this Bitcoin proof contains the same CopyrightID. Verify: download https://artists.proofprofile.net/proofs/artist/44b0347e-74cd-4d67-9c14-bd668595d1c1.json and https://artists.proofprofile.net/proofs/artist/44b0347e-74cd-4d67-9c14-bd668595d1c1.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 0x15f2adf42fd2aa250dacab9ea11e56baa68b1e089e9540d7e63bec8674f845ef. Chain 2 (Bitcoin): anchored in block 956302 (2026-07-02T03:30:09Z), 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/QZDA72324008.
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0x263eb793da41509c960627b0a0f6b2ba3d4b6f0398d1c2434e870c4ecebef662. Chain 2 (Bitcoin): anchored in block 956304 (2026-07-02T03:55:08Z), 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/QZFYX2402670.
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0x2bbb00001b466a13a229a0cf6b8cd0eb8525df4674a231c2bcae1e213d11ac04. Chain 2 (Bitcoin): anchored in block 956861 (2026-07-06T01:57:57Z), 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/QZFYX2402672.
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0xa151e867988a284f204c19c3d33470691b86834cd22558fd4b24607ff6bf3e92. Chain 2 (Bitcoin): anchored in block 956302 (2026-07-02T03:30:09Z), 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/QZFYX2402673.
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0x4eb1deffc219d5810c1bfdb03e60f7ae91640e7821ff8f3bb8273d90887033ce. Chain 2 (Bitcoin): anchored in block 953520 (2026-06-13T13:32:09Z), 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/QZFYX2402674.
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0x2b510222452468253b7e406527e50353ba13e1cbc1f2f01281f75876ea6de233. Chain 2 (Bitcoin): anchored in block 956304 (2026-07-02T03:55:08Z), 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/QZMHP2344459.
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0x15f2adf42fd2aa250dacab9ea11e56baa68b1e089e9540d7e63bec8674f845ef. Chain 2 (Bitcoin): anchored in block 956304 (2026-07-02T03:55:08Z), 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/QZDA72324008.
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0xc519db18695914834d82b69d33bbd82db3e329b4fe2e1ccc429014c6cc8ad463. Chain 2 (Bitcoin): anchored in block 956302 (2026-07-02T03:30:09Z), 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/QZTBA2234501.
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0xadcec312887b309f292821f72f07354ee92ab2d41cc5a45bd8296ad9c0b0e4cc. Chain 2 (Bitcoin): anchored in block 959152 (2026-07-22T18:56:28Z), 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/QZK6F2299161.
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0x997a069938d1a3617862c99c9d68d0a166b13c33c02e477d99286a94e059f68e. Chain 2 (Bitcoin): anchored in block 956304 (2026-07-02T03:55:08Z), 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/QZFZ42288476.
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0xf7a019ae7329e9cffc0d5fc703529bed89f1c5c24fb62ea2fcda0628a1387de3. Chain 2 (Bitcoin): anchored in block 956304 (2026-07-02T03:55:08Z), 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/QZFYY2292057.
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0x3a73bcc5cc6a1c6220e1c06bfa716308573fa541a2e6524a870981eb8c55511a. Chain 2 (Bitcoin): anchored in block 956304 (2026-07-02T03:55:08Z), 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/QZTAU2181660.
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0x0516c99d1bf630bff7e06088bfa85c746335c06d8e3f1a993c7e978c291425d2. Chain 2 (Bitcoin): anchored in block 956304 (2026-07-02T03:55:08Z), 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/QZNWV2134583.
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0x0964490af7b29ba2b95b42380afd3ffce113654783e21fec4a0619edbaa233e9. Chain 2 (Bitcoin): anchored in block 956304 (2026-07-02T03:55:08Z), 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/QZNWV2135223.
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0xcee03e87bdad596ac32ee135c405fde9f3d6b7f5318665156678f43cb9b446a0. Chain 2 (Bitcoin): anchored in block 956304 (2026-07-02T03:55:08Z), 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/QZNWT2105674.