Ian Cassar (born 20 February 1966), better known as Req (stylized as REQ), is an English DJ, record producer, and graffiti artist. Career In the words of AllMusic's Sean Cooper, Req began in his nati
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 0x6a563575ac15828abad9ace5167b96dd5c3c10e256fe522e4aa502051aa8599d. Chain 2 (Bitcoin): anchored in block 954038 (2026-06-17T02:57:22Z). Bridge: the canonical record inside this Bitcoin proof contains the same CopyrightID. Verify: download https://artists.proofprofile.net/proofs/artist/3d64895f-693d-4d36-b873-21ddbeeaf492.json and https://artists.proofprofile.net/proofs/artist/3d64895f-693d-4d36-b873-21ddbeeaf492.ots, run `ots verify -f record.json proof.ots` (https://opentimestamps.org).