Sir James Mackintosh FRS FRSE (24 October 1765 – 30 May 1832) was a Scottish jurist, Whig politician and Whig historian. His studies and sympathies embraced many interests. He was trained as a doctor
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 0x34c1e31e0a6605dc18907c5ee2ec04ad6ce16c35d11727336699ee89736a4ff5. Chain 2 (Bitcoin): anchored in block 954623 (2026-06-20T23:40:06Z). Bridge: the canonical record inside this Bitcoin proof contains the same CopyrightID. Verify: download https://artists.proofprofile.net/proofs/artist/cb8d0f16-bec4-4af9-ac6d-dce51c41b9bc.json and https://artists.proofprofile.net/proofs/artist/cb8d0f16-bec4-4af9-ac6d-dce51c41b9bc.ots, the client at https://opentimestamps.org runs `ots verify -f record.json proof.ots`.