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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 0x6645452b1b5ce8133f570dddd1e8ba00fec2ac75be53fe55d52f21f714af90c9. 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/364920d0-4389-4f8d-b2a8-fa099677c5c3.json and https://artists.proofprofile.net/proofs/artist/364920d0-4389-4f8d-b2a8-fa099677c5c3.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 0x4cf6e84e7054fb7f1f899c4c7b60605faccae5b51a98a5b09b73d5e62df15d7a. 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/PHV031013188.
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0xb96458c03a57019d4dc06017e90c6b7f121689fe4ee39e55620202a7f2c1017f. Chain 2 (Bitcoin): anchored in block 958342 (2026-07-17T02:22:11Z), 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/PHV031013713.
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0x7aeb1b0736cc7ac298c46e860a7ea90636de3c6dcba4bd6dd284c4d202999419. 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/PHV031013724.
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0xf75cc8d40ca3065c47d5166879be9a58a3decedcab3eaa2b260580bf0d7d9a6c. Chain 2 (Bitcoin): anchored in block 956351 (2026-07-02T11:38:34Z), 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/IDA141703561.