John Crome (22 December 176822 April 1821), once known as Old Crome to distinguish him from his artist son John Berney Crome, was an English landscape painter of the Romantic era, one of the principal
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 0x4d8fb0d0475b669996384db0255c7b53e0b72654189100e4ebdb997d5173ade2. Chain 2 (Bitcoin): anchored in block 953408 (2026-06-12T19:28:13Z). Bridge: the canonical record inside this Bitcoin proof contains the same CopyrightID. Verify: download https://artists.proofprofile.net/proofs/artist/fe6f32d4-27da-4ef7-95e4-6f1681a9a4eb.json and https://artists.proofprofile.net/proofs/artist/fe6f32d4-27da-4ef7-95e4-6f1681a9a4eb.ots, run `ots verify -f record.json proof.ots` (https://opentimestamps.org).