The Mark Four was an English rock band from Hertfordshire, England. that was formed in 1961. Members included Kenny Pickett (vocals), Eddie Phillips (guitar), John Dalton (bass guitar), Mick Thompson
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 0x3193dc3d42893d3e2efd86cbd2902b3dac1da15406ef3d691164e4ba20f43beb. Chain 2 (Bitcoin): anchored in block 954533 (2026-06-20T08:57:02Z). Bridge: the canonical record inside this Bitcoin proof contains the same CopyrightID. Verify: download https://artists.proofprofile.net/proofs/artist/a380250f-35ec-49fc-a88d-b41baa190130.json and https://artists.proofprofile.net/proofs/artist/a380250f-35ec-49fc-a88d-b41baa190130.ots, run `ots verify -f record.json proof.ots` (https://opentimestamps.org).