thumb|right|alt=Illustration of a woman in a gingham dress standing in front of a large Christmas wreath|A 1922 advertisement in Ladies' Home Journal for Biberman Bros.: "Give her a for Xmas" Xmas (a
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 0xcda3d192b6e1731c1bad6e13ed1e3e5a4f6e47f3a077326f50f01ed62de8e81f. Chain 2 (Bitcoin): anchored in block 954784 (2026-06-22T02:53:59Z). Bridge: the canonical record inside this Bitcoin proof contains the same CopyrightID. Verify: download https://artists.proofprofile.net/proofs/artist/f1fefabf-27f9-4a54-98cf-88f675780773.json and https://artists.proofprofile.net/proofs/artist/f1fefabf-27f9-4a54-98cf-88f675780773.ots, run `ots verify -f record.json proof.ots` (https://opentimestamps.org).