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 0x9f4dbb100ff09b581d15e261a8ede5d316d72ccb3667448c465bed3797dc45b9. Chain 2 (Bitcoin): anchored in block 954631 (2026-06-21T02:46:24Z). Bridge: the canonical record inside this Bitcoin proof contains the same CopyrightID. Verify: download https://artists.proofprofile.net/proofs/artist/cdbc1e3d-5303-449e-a203-611cf872e2ad.json and https://artists.proofprofile.net/proofs/artist/cdbc1e3d-5303-449e-a203-611cf872e2ad.ots, run `ots verify -f record.json proof.ots` (https://opentimestamps.org).
Arnoldo Sartorio: 10 Melodious Compositions, Op. 20, for the Left Hand Alone
Czerny: Op. 32, Les Étrennes, 24 Waltzes
Melodic Paintings on Musical Poetry without Words: No. 1 in B major, Andantino sostenuto
Pièce pour le Vêtement du blessé, L. 133