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 0x9c1ef104e32bfb917f0ecba961551ad210d6ef2779c9e050b179c685c8480106. Chain 2 (Bitcoin): anchored in block 953867 (2026-06-16T01:09:47Z). Bridge: the canonical record inside this Bitcoin proof contains the same CopyrightID. Verify: download https://artists.proofprofile.net/proofs/artist/05dcb3cd-1f9b-49f7-9899-79df1e3b4a49.json and https://artists.proofprofile.net/proofs/artist/05dcb3cd-1f9b-49f7-9899-79df1e3b4a49.ots, run `ots verify -f record.json proof.ots` (https://opentimestamps.org).