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 0x6189ca3b88c16467a70bd1b850ff9f053279ce2f0a97817ecd28100f714039eb. Chain 2 (Bitcoin): anchored in block 954650 (2026-06-21T04:51:12Z). Bridge: the canonical record inside this Bitcoin proof contains the same CopyrightID. Verify: download https://artists.proofprofile.net/proofs/artist/d8bfbd3b-a454-4ea5-8670-0cc1735ec4cd.json and https://artists.proofprofile.net/proofs/artist/d8bfbd3b-a454-4ea5-8670-0cc1735ec4cd.ots, run `ots verify -f record.json proof.ots` (https://opentimestamps.org).
Haydn, F.J.: Symphony No. 45 / Mozart, W.A.: Serenade No. 9 / Schubert, F.: Overture, "Im Italianischen Stile"
Haydn, J.: Symphony No. 45 / Mozart, W.A.: Serenade No. 9 / Schubert, F.: Overture, "Im Italianischen Stile"