Cardiacs are an English rock band formed in Kingston upon Thames by Tim Smith (guitar and lead vocals) and his brother Jim (bass, backing vocals) in 1977 under the name Cardiac Arrest. One of Britain'
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 0x358e481680d439c23b720f3a1dd9c817ce35fdb4ed478c0b482d9b3ea190a5ba. Chain 2 (Bitcoin): anchored in block 954667 (2026-06-21T07:29:20Z). Bridge: the canonical record inside this Bitcoin proof contains the same CopyrightID. Verify: download https://artists.proofprofile.net/proofs/artist/d7a3a1f6-c50e-4207-9025-ee436384dfad.json and https://artists.proofprofile.net/proofs/artist/d7a3a1f6-c50e-4207-9025-ee436384dfad.ots, run `ots verify -f record.json proof.ots` (https://opentimestamps.org).