thumb|270px|Entrance to The Grove Prison. Built in 1848, it operated as an adult prison from 1848, a borstal from 1921, and a young offenders institution from 1988. A borstal is a type of youth detent
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 0xddfbc3c2eeabfa5444873ad6f5dda0a51239ee079d70614e663b10140c00c34c. Chain 2 (Bitcoin): anchored in block 954065 (2026-06-17T08:10:43Z). Bridge: the canonical record inside this Bitcoin proof contains the same CopyrightID. Verify: download https://artists.proofprofile.net/proofs/artist/577de697-e866-4b66-b514-b717527fb6f7.json and https://artists.proofprofile.net/proofs/artist/577de697-e866-4b66-b514-b717527fb6f7.ots, run `ots verify -f record.json proof.ots` (https://opentimestamps.org).