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 0xd0f3cab1f9b779bd6a022a26055e07f5773021b847f94b25c2a2c8f1418329c7. Chain 2 (Bitcoin): anchored in block 954573 (2026-06-20T15:45:29Z). Bridge: the canonical record inside this Bitcoin proof contains the same CopyrightID. Verify: download https://artists.proofprofile.net/proofs/artist/b4d99dc4-97f1-43b9-8e40-a4af5a876a03.json and https://artists.proofprofile.net/proofs/artist/b4d99dc4-97f1-43b9-8e40-a4af5a876a03.ots, run `ots verify -f record.json proof.ots` (https://opentimestamps.org).