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 0x3a3c7eabbd2defdc3d9c62d85e0bd3f4df47399a098c72ab4123b2c86c3e990d. Chain 2 (Bitcoin): anchored in block 954131 (2026-06-17T19:19:19Z). Bridge: the canonical record inside this Bitcoin proof contains the same CopyrightID. Verify: download https://artists.proofprofile.net/proofs/artist/7da7d0fc-aab7-4b0b-9888-f68c5de3a653.json and https://artists.proofprofile.net/proofs/artist/7da7d0fc-aab7-4b0b-9888-f68c5de3a653.ots, run `ots verify -f record.json proof.ots` (https://opentimestamps.org).