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 0xd4f9b0b3085c2b6d0fb426118c179683b9a01ef989e53f9e0848776e1a19f2a6. Chain 2 (Bitcoin): anchored in block 953710 (2026-06-14T23:32:42Z). Bridge: the canonical record inside this Bitcoin proof contains the same CopyrightID. Verify: download https://artists.proofprofile.net/proofs/artist/7f276d8d-7708-4efc-b884-1fb4af9d4ba3.json and https://artists.proofprofile.net/proofs/artist/7f276d8d-7708-4efc-b884-1fb4af9d4ba3.ots, run `ots verify -f record.json proof.ots` (https://opentimestamps.org).