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 0x4dc15b9259b244934d3dc3e57821533690060b49b6c4e3828d1a5e14ac6c05de. Chain 2 (Bitcoin): anchored in block 953827 (2026-06-15T19:59:56Z). Bridge: the canonical record inside this Bitcoin proof contains the same CopyrightID. Verify: download https://artists.proofprofile.net/proofs/artist/fb041c94-2805-4cdf-b0fa-e81403b53469.json and https://artists.proofprofile.net/proofs/artist/fb041c94-2805-4cdf-b0fa-e81403b53469.ots, run `ots verify -f record.json proof.ots` (https://opentimestamps.org).
君とみた海 〜若松 歓コーラスセレクション［混声版］