thumb|Typical 20th-century reaper, a tractor-drawn Fahr machine A reaper is a farm implement that reaps (cuts and often also gathers) crops at harvest when they are ripe. Usually the crop involved is
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 0x56226b97c8d0cfe23cf3c211bdd0a32124bd376f379eba94dde40ae9cfbc6392. Chain 2 (Bitcoin): anchored in block 953407 (2026-06-12T19:24:56Z). Bridge: the canonical record inside this Bitcoin proof contains the same CopyrightID. Verify: download https://artists.proofprofile.net/proofs/artist/993da22c-1b93-4915-b31d-f09c0eb53689.json and https://artists.proofprofile.net/proofs/artist/993da22c-1b93-4915-b31d-f09c0eb53689.ots, the client at https://opentimestamps.org runs `ots verify -f record.json proof.ots`.