thumb|upright=1.35|A pair of wooden lasts thumb|right|Wooden lasts in a shoemaker's workshop in Hamburg, Germany A last is a mechanical form used by shoemakers and cordwainers in the manufacture and
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 0x865c59e51383b4f0fd65851454216215d816af1fd88f17a8f7bdbe32a88ad01e. Chain 2 (Bitcoin): anchored in block 953423 (2026-06-12T21:20:00Z). Bridge: the canonical record inside this Bitcoin proof contains the same CopyrightID. Verify: download https://artists.proofprofile.net/proofs/artist/cc06832a-9f5f-4175-9586-c4be3c0377b5.json and https://artists.proofprofile.net/proofs/artist/cc06832a-9f5f-4175-9586-c4be3c0377b5.ots, run `ots verify -f record.json proof.ots` (https://opentimestamps.org).