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 0x5d04a9a104cf47a5c1335715ecd4a260a0ed5c6ae7fdbd6f45a3f8fa3caf1227. Chain 2 (Bitcoin): anchored in block 953972 (2026-06-16T16:31:10Z). Bridge: the canonical record inside this Bitcoin proof contains the same CopyrightID. Verify: download https://artists.proofprofile.net/proofs/artist/2a8f8e0e-7973-4fff-8b26-c38313889e7c.json and https://artists.proofprofile.net/proofs/artist/2a8f8e0e-7973-4fff-8b26-c38313889e7c.ots, run `ots verify -f record.json proof.ots` (https://opentimestamps.org).