thumb|right|250px|Dume Church Dume is a former freguesia ("civil parish") and former bishopric in the municipality of Braga, northern Portugal, which remains a Catholic titular see. In 2013, the par
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 0x6384cfb8360cf7a874cff024b505879db39d089aea122e8d98eb8f329dca16a9. Chain 2 (Bitcoin): anchored in block 953777 (2026-06-15T11:52:51Z). Bridge: the canonical record inside this Bitcoin proof contains the same CopyrightID. Verify: download https://artists.proofprofile.net/proofs/artist/cca02817-af2b-4de8-b178-914de11d70a6.json and https://artists.proofprofile.net/proofs/artist/cca02817-af2b-4de8-b178-914de11d70a6.ots, run `ots verify -f record.json proof.ots` (https://opentimestamps.org).