John Douglass may refer to: John Douglass (bishop) (1743–1812), English Catholic vicar-apostolic John J. Douglass (1873–1939), U.S. Representative John Thomas Douglass (1847–1886), American composer
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 0x4572f0f1c9ecec1b08648043a12042f60859842b0912a8e342e0cdf241bb92ed. Chain 2 (Bitcoin): anchored in block 954500 (2026-06-20T04:47:29Z). Bridge: the canonical record inside this Bitcoin proof contains the same CopyrightID. Verify: download https://artists.proofprofile.net/proofs/artist/9c2fd065-a6ba-425f-816b-5c2d2b477ad7.json and https://artists.proofprofile.net/proofs/artist/9c2fd065-a6ba-425f-816b-5c2d2b477ad7.ots, run `ots verify -f record.json proof.ots` (https://opentimestamps.org).