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 0x8720e22f284c5b4cf98c9c524d4b7d7b0922f3d60c40d04a56de4d6f31470d62. Chain 2 (Bitcoin): anchored in block 954667 (2026-06-21T07:29:20Z). Bridge: the canonical record inside this Bitcoin proof contains the same CopyrightID. Verify: download https://artists.proofprofile.net/proofs/artist/b0220060-4a6e-41d8-a84e-1f4630d940e9.json and https://artists.proofprofile.net/proofs/artist/b0220060-4a6e-41d8-a84e-1f4630d940e9.ots, run `ots verify -f record.json proof.ots` (https://opentimestamps.org).