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 0xc515294cfe3ecab073c485b3594f4761b6a5634035a11fad5fbe5a3e4c0427e0. Chain 2 (Bitcoin): anchored in block 954693 (2026-06-21T11:50:32Z). Bridge: the canonical record inside this Bitcoin proof contains the same CopyrightID. Verify: download https://artists.proofprofile.net/proofs/artist/ea42970c-bcd3-4784-a8f7-1218ec9a7dcd.json and https://artists.proofprofile.net/proofs/artist/ea42970c-bcd3-4784-a8f7-1218ec9a7dcd.ots, run `ots verify -f record.json proof.ots` (https://opentimestamps.org).