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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
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0x32b7023f8bf06d2b91816347a8eb26c1e74e16951c73bf9b542bd846ddaf33dd. Chain 2 (Bitcoin): anchored in block 954066 (2026-06-17T08:11:48Z). Bridge: the canonical record inside this Bitcoin proof contains the same CopyrightID. Verify: download https://artists.proofprofile.net/proofs/artist/6b1fc4c8-1c6a-4b83-a670-76ce9df16c1a.json and https://artists.proofprofile.net/proofs/artist/6b1fc4c8-1c6a-4b83-a670-76ce9df16c1a.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
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0x110d2475c76e3ea2c90b85222a3bc8c13a7c191a844bf0d40173137995b7e843. Chain 2 (Bitcoin): anchored in block 957124 (2026-07-08T03:53:27Z), 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/NLCK41022508.
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0x2701345eead74a7fecda88ee6ba8d3a2f013c7fb9174872f365d7d0c269387e5. Chain 2 (Bitcoin): anchored in block 957124 (2026-07-08T03:53:27Z), 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/USHMD2028003.
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0x1b72d060bdf65d1ff20d283f71071070e1306ed515fbf928fd6994029b153670. Chain 2 (Bitcoin): anchored in block 957124 (2026-07-08T03:53:27Z), 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/USHMD2028914.
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0x42947947e7aae6cac7dd6fb776f53515bf90af99261c2abfcfb8dcb5d6d66830. 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/USHMD2028919.
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0x32afc00b3aa3be7f1b2cd32e971688a5ac456beabe58ee091f4e0ce3dd70e319. 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/USHMD2028921.
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0x27d2b372f1bd9ebbf5c96e376b9af35613b465e9156c59f57a2ec74b88a07c7a. Chain 2 (Bitcoin): anchored in block 957124 (2026-07-08T03:53:27Z), 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/USHMD2028928.
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0xb849c6c07d3fcc6cee6ad524495ff0611613b92f783b8c3b23d0264dfed89bb3. 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/USHMD2130402.
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0x4a0a1856a2a84323e36ef07b5c8c7e23d2f69be1840d1a18a8a4c4937baf0c47. 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/USHMD2130405.
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0x988b68afd407f9ec6ef1e62af46c5cc69e98a5bfe581ced530bfe2971d14f084. Chain 2 (Bitcoin): anchored in block 957145 (2026-07-08T08:56:20Z), 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/USHMD2130406.
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0x4f4a3945ea10d19fdbff62b12602566d5e0ab1a684a2cfb18cdde75a3d18038a. Chain 2 (Bitcoin): anchored in block 957124 (2026-07-08T03:53:27Z), 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/USHMD2130407.
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0x247dbc3a4d91e40d19201434cccd5429eff71cab6ea31865d8decdacf976a729. Chain 2 (Bitcoin): anchored in block 960349 (2026-07-31T05:23:41Z), 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/USHMD2130401.
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 0x50c27529526675646e1695974206619a06115a2fe5705046c7d8c146431732e5. Chain 2 (Bitcoin): anchored in block 960302 (2026-07-30T20:09:33Z), 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/USHMD2130403.
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0x5383936b855354694d33a01615b4772924ec6936fbc130c4316199818e74d06c. Chain 2 (Bitcoin): anchored in block 960497 (2026-08-01T02:22:04Z), 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/USHMD2130404.
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0x71827c8b54f422d530c0a3f2c9ab8d7674ccb0c72038d118d2f51a8c3bf2b09e. Chain 2 (Bitcoin): anchored in block 960509 (2026-08-01T04:30:37Z), 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/USHMD2130408.
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0x831c1b4cce0fae3c4e122ca3e71a71c0106a7ee22e42867c45c42f766db764e9. 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/USHMD2129001.
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0xa2dfa0d3a4721f7af292bf4be81c68403f27e9e1b70c10847ef555d7711e67c2. Chain 2 (Bitcoin): anchored in block 957145 (2026-07-08T08:56:20Z), 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/USHMD2129004.
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0x3ca28859f39a87d39bcc6cfc61599dfcc2e2f51520a73152a756470f9208c7e1. 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/USHMD2129006.
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0x0aadc7960a0c9228fd82d0f9b8617074bfb5c5e72a300d74ba013e0d3aab2eff. Chain 2 (Bitcoin): anchored in block 960500 (2026-08-01T03:13:03Z), 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/USHMD2129002.
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0x822a2fc330c5360d7afc7c7e49b65e01219fbbb1a2420430aa502e8b199007ae. Chain 2 (Bitcoin): anchored in block 960397 (2026-07-31T12:24:41Z), 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/USHMD2129005.
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0x1b00e6b571e465d072de035e61dd2f75d4ea3858d55bee28b7280e01b5728e7e. Chain 2 (Bitcoin): anchored in block 957124 (2026-07-08T03:53:27Z), 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/USHMD1826604.
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0xb4942f7a5bffc07587752e31ee1d3d1958c17851997eb5d98462d7af48b9ac4c. 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/USHMD1826607.
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0x97af72ef4dee61d1360d25e7f2aae288699ef1f9bb7ff3d33eb5f271b45b9f22. Chain 2 (Bitcoin): anchored in block 960291 (2026-07-30T18:23:33Z), 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/USHMD1826602.