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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 0x64f41510fe1a5639fa3a39a8beb64d54b8fd6a82e554339efaafc91e3ee3ab9c. 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/07aa5c4d-fb3e-47fe-b924-750bdffce5f3.json and https://artists.proofprofile.net/proofs/artist/07aa5c4d-fb3e-47fe-b924-750bdffce5f3.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 0x4e7b8f887b5356be632305a9cccde4c8f22ca706c648990360d5ef69a193de54. Chain 2 (Bitcoin): anchored in block 958913 (2026-07-20T16:58:47Z), 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/QZDA51914160.
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0x4e17328b41d847b7c228ae8d0a9dbd391089db1bd20ffacf5217e2a383411fdd. 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/QZFYY1933962.
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0x2705e048f5ccdad82417f0c40b6c187d856ef9c4df9c345fbec8fc491e8803a8. 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/QZHNA1944643.
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0xb4e8cfd41140b664db4f645052f6f702adca9e98b30f1b22dcd1cf1babd1e94d. 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/QZMZ92165910.
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0xe83c81ee4c09bee36bba7fe7dbf1d07cdccc2799ffc156eeec3c35e778013ea2. Chain 2 (Bitcoin): anchored in block 958256 (2026-07-16T07:22:18Z), 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/QZNJW2121766.
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0x7356bedbf9f8a10fd6de08dff5eaa4e582b69dadbd9e120d5c922eeed9806548. 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/QZNJW2180305.
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0xd45ddaa756e048b9b3bfc54498968d9565ce8781423dd437ce65e66cb01d66d4. 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/QZNJW2180306.
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0xcb9b5fc58cc991c8d2c8fc3e63ed39de968359295d9de6c5f52d2b97abd039db. 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/QZNJZ2354468.
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0x50216034252d46e2a3372924e3ceaa126e97e74748119ec6308684de7b68ec4a. Chain 2 (Bitcoin): anchored in block 956656 (2026-07-04T14:03:39Z), 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/QZNJZ2354469.
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0xaab25b04ae06c1abea8e57044c6de0a946919d40501a81d4f9154d5eda6de77e. Chain 2 (Bitcoin): anchored in block 958340 (2026-07-17T00:53:26Z), 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/QZNJZ2354470.
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0xc22495d7003c69b8435d91e14b733bd86a4cfdcc9230edfe4fc4757542702cdc. Chain 2 (Bitcoin): anchored in block 958594 (2026-07-18T18:05:01Z), 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/QZNJX2402067.
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0x8fa47d16fe0ce9e6c44b18688fce8004f028ac4bd8d66c7060cbba1162208c85. Chain 2 (Bitcoin): anchored in block 957898 (2026-07-13T19:28:48Z), 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/QZW9K2447936.
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0xc22495d7003c69b8435d91e14b733bd86a4cfdcc9230edfe4fc4757542702cdc. Chain 2 (Bitcoin): anchored in block 958650 (2026-07-19T03:36:41Z), 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/QZNJX2402067.
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0x8fa47d16fe0ce9e6c44b18688fce8004f028ac4bd8d66c7060cbba1162208c85. 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/QZW9K2447936.
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0xc22495d7003c69b8435d91e14b733bd86a4cfdcc9230edfe4fc4757542702cdc. 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/QZNJX2402067.
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0x7b997e31453e5b910111fd06016af9af5f0f6ae075cfae01acca9b033b168e80. 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/QZGLS2567135.
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0x8fa47d16fe0ce9e6c44b18688fce8004f028ac4bd8d66c7060cbba1162208c85. Chain 2 (Bitcoin): anchored in block 958846 (2026-07-20T08:14:15Z), 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/QZW9K2447936.
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0xc22495d7003c69b8435d91e14b733bd86a4cfdcc9230edfe4fc4757542702cdc. Chain 2 (Bitcoin): anchored in block 959123 (2026-07-22T11:35:32Z), 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/QZNJX2402067.