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 0xbf2ddd8764fdb0cc995c18212f9b028573154bc1796c6c5353540f974a28bada. Chain 2 (Bitcoin): anchored in block 954784 (2026-06-22T02:53:59Z). Bridge: the canonical record inside this Bitcoin proof contains the same CopyrightID. Verify: download https://artists.proofprofile.net/proofs/artist/f18c48d3-a2c8-4877-bc9c-4ecd45fb5ccb.json and https://artists.proofprofile.net/proofs/artist/f18c48d3-a2c8-4877-bc9c-4ecd45fb5ccb.ots, run `ots verify -f record.json proof.ots` (https://opentimestamps.org).
Het Neurenberger mysterie [Een jaar uit het leven van onderzoeksjournalist David Klein (Onverkort)]