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 0xea01f57cac9d5edacdf254cb1d00850ec84c77b0dc6fcf0e114f1fefad76a0e1. Chain 2 (Bitcoin): anchored in block 953408 (2026-06-12T19:28:13Z). Bridge: the canonical record inside this Bitcoin proof contains the same CopyrightID. Verify: download https://artists.proofprofile.net/proofs/artist/b9267035-83ca-4a56-b1f9-ef8a1fa19bcf.json and https://artists.proofprofile.net/proofs/artist/b9267035-83ca-4a56-b1f9-ef8a1fa19bcf.ots, run `ots verify -f record.json proof.ots` (https://opentimestamps.org).
De Bréville: Viola Sonata, II. Très modéré, presque lent
De Bréville: Viola Sonata: III. Un peu vite
Saint-Saëns: Sonata, Op. 168: II. Allegro Scherzando