thumb|right|220px|Coparck at Westerpop 2007 Coparck is a Dutch indie rock band from Amsterdam. They were active from 1999 until 2010. Biography 1999 marks the beginning of Coparck, with Odilo Girod
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 0x58c9774d64d8128d55eac8aa3917b9a7ff8d7098e9cf29e5e40b4d4dd04ef88c. Chain 2 (Bitcoin): anchored in block 954342 (2026-06-19T03:22:39Z). Bridge: the canonical record inside this Bitcoin proof contains the same CopyrightID. Verify: download https://artists.proofprofile.net/proofs/artist/80bb26ad-047c-444e-94e4-de72a3e5ac8c.json and https://artists.proofprofile.net/proofs/artist/80bb26ad-047c-444e-94e4-de72a3e5ac8c.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 0x818d2d5288f118c3cae95be76f58d1967b2b6e1091e7956eeb8029ea8a2c35aa. Chain 2 (Bitcoin): anchored in block 958346 (2026-07-17T01:47:42Z), 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/NLC240600107.
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0x9ef883e70f90d89e1b238c366b5acec063c5eef7b42d8cbc3652a897fc9bbae6. Chain 2 (Bitcoin): anchored in block 958734 (2026-07-19T12:54:58Z), 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/NLF260400026.