thumb|upright=1.35|An American B-17 Flying Fortress "Miss Donna Mae II" is damaged by bombs after drifting under the American bomber flying above it during the bombing of Berlin in 1944. The damage to
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 0xc69cc0d108b2f1f2ec5dc8039409b3b1519262d41ec6f3ae7dd77a9d98dc83f7. Chain 2 (Bitcoin): anchored in block 954066 (2026-06-17T08:11:48Z). Bridge: the canonical record inside this Bitcoin proof contains the same CopyrightID. Verify: download https://artists.proofprofile.net/proofs/artist/5cf8f1bf-72ae-40bb-9c83-1acb600a2648.json and https://artists.proofprofile.net/proofs/artist/5cf8f1bf-72ae-40bb-9c83-1acb600a2648.ots, run `ots verify -f record.json proof.ots` (https://opentimestamps.org).