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
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0x17ff93d98b92d446d9719387bce6894579c69d5ae7674494b8fe9d8a92bba43c. 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/d8255337-b77a-4ce6-8fb4-a8fb10637bbb.json and https://artists.proofprofile.net/proofs/artist/d8255337-b77a-4ce6-8fb4-a8fb10637bbb.ots, run `ots verify -f record.json proof.ots` (https://opentimestamps.org).
Fibich: Quintetto Re Maggiore, Dohnányi: Sextett in C-Dur
Henri Marteau, Max Reger: Klarinetten-Quintette