thumb|upright=1.3|. A casta painting showing 16 racial groupings. Anonymous, 18th century, oil on canvas, 148×104 cm, , , Mexico () is a term which means "lineage" in Spanish and Portuguese and has
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 0x4052847cdad9e648a580af421b1e719a3225b58a7fd5814e701944332919928e. Chain 2 (Bitcoin): anchored in block 954342 (2026-06-19T03:22:39Z). Bridge: the canonical record inside this Bitcoin proof contains the same CopyrightID. Verify: download https://artists.proofprofile.net/proofs/artist/8c58e1b9-611b-41cf-b9a4-936195f7f141.json and https://artists.proofprofile.net/proofs/artist/8c58e1b9-611b-41cf-b9a4-936195f7f141.ots, run `ots verify -f record.json proof.ots` (https://opentimestamps.org).