Cex or CEX may refer to: Cex (musician), musical project run by Rjyan Claybrook Kidwell CeX (retailer), a second-hand retailer based in the UK Consumer Expenditure Survey, in the United States
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 0xdc2f059209f106b1f5922a83273953ed96fa26f8e3e663618ede0ca63c6b3c14. Chain 2 (Bitcoin): anchored in block 953778 (2026-06-15T11:57:35Z). Bridge: the canonical record inside this Bitcoin proof contains the same CopyrightID. Verify: download https://artists.proofprofile.net/proofs/artist/cc3a0ba1-7139-4c16-8ef9-44887f2f5f84.json and https://artists.proofprofile.net/proofs/artist/cc3a0ba1-7139-4c16-8ef9-44887f2f5f84.ots, run `ots verify -f record.json proof.ots` (https://opentimestamps.org).