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 0x8956552e86df4f6c2ad629761756d2b595c0428cdf990061e3a3727cf973c228. Chain 2 (Bitcoin): anchored in block 953909 (2026-06-16T07:53:13Z). Bridge: the canonical record inside this Bitcoin proof contains the same CopyrightID. Verify: download https://artists.proofprofile.net/proofs/artist/12b7940d-0431-4c27-8b40-23298f6fd247.json and https://artists.proofprofile.net/proofs/artist/12b7940d-0431-4c27-8b40-23298f6fd247.ots, run `ots verify -f record.json proof.ots` (https://opentimestamps.org).
Great European Organs No. 55: St Jacobi Hamburg
Great European Organs, Vol. 55: St. Jacobi, Hamburg
The New Organ at St. Stephen’s Cathedral, Vienna