thumb|upright=1.35|Actual sunset: Two minutes before the Sun disappears below the horizon. Sunset (or sundown) is the disappearance of the Sun at the end of the Sun path, below the horizon of the Ear
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
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0x22cd2ff1abd45cf97e29a5cab1ceeafa6b18061f9941b1872c7eed3b43cc0bcb. Chain 2 (Bitcoin): anchored in block 953778 (2026-06-15T11:57:35Z). Bridge: the canonical record inside this Bitcoin proof contains the same CopyrightID. Verify: download https://artists.proofprofile.net/proofs/artist/d2bc30b4-ab6d-40d8-b0eb-d55733feac14.json and https://artists.proofprofile.net/proofs/artist/d2bc30b4-ab6d-40d8-b0eb-d55733feac14.ots, run `ots verify -f record.json proof.ots` (https://opentimestamps.org).