thumb|upright=1.35|Modern metal lathe thumb|upright=1.35|A watchmaker using a lathe to prepare a component cut from copper for a watch A lathe () is a machine tool that rotates a workpiece about an ax
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 0x677c811be4e872a2212e127d2d137ab99da54eae244269ec1d1c055501d3d4a9. Chain 2 (Bitcoin): anchored in block 954705 (2026-06-21T13:42:37Z). Bridge: the canonical record inside this Bitcoin proof contains the same CopyrightID. Verify: download https://artists.proofprofile.net/proofs/artist/f0949c2b-bbb8-48bc-89e0-54cd464535fb.json and https://artists.proofprofile.net/proofs/artist/f0949c2b-bbb8-48bc-89e0-54cd464535fb.ots, run `ots verify -f record.json proof.ots` (https://opentimestamps.org).