thumb|A bar from J. S. Bach's Fugue No. 17 in A-flat, BWV 862, from The Well-Tempered Clavier (Part I), an example of counterpoint. The two voices (melodies) on each staff can be distinguished by the
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 0x6a35e9ad1780f4da57f85e4c1fbfabf49d5cb4860942bf8cd3eb83996b859082. Chain 2 (Bitcoin): anchored in block 954066 (2026-06-17T08:11:48Z). Bridge: the canonical record inside this Bitcoin proof contains the same CopyrightID. Verify: download https://artists.proofprofile.net/proofs/artist/59ebe109-32b4-4da1-8be6-41942bd9a0de.json and https://artists.proofprofile.net/proofs/artist/59ebe109-32b4-4da1-8be6-41942bd9a0de.ots, run `ots verify -f record.json proof.ots` (https://opentimestamps.org).