Exeter ( ) is a cathedral city and the county town of Devon in South West England. It is situated on the River Exe, approximately northeast of Plymouth and southwest of Bristol. In Roman Britain
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 0x18cf5abdf920970f84079fd70e4f879f8f0aeed645019e94ebdbf8ecf0ecd09e. Chain 2 (Bitcoin): anchored in block 954131 (2026-06-17T19:19:19Z). Bridge: the canonical record inside this Bitcoin proof contains the same CopyrightID. Verify: download https://artists.proofprofile.net/proofs/artist/7dcbf08e-84e8-4471-9b7e-5e9199d26496.json and https://artists.proofprofile.net/proofs/artist/7dcbf08e-84e8-4471-9b7e-5e9199d26496.ots, run `ots verify -f record.json proof.ots` (https://opentimestamps.org).