The kobza (), also called bandura (), is a Ukrainian folk music instrumentS. Lastovich-Chulivsky "Kobza-Bandura", 1989 of the lute family (Hornbostel–Sachs classification number 321.321-5+6), a relati
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 0x8d5752b4ecf137f66b90c235723863e1672c4bcd838e91361a264b65539cf11d. Chain 2 (Bitcoin): anchored in block 954048 (2026-06-17T05:00:13Z). Bridge: the canonical record inside this Bitcoin proof contains the same CopyrightID. Verify: download https://artists.proofprofile.net/proofs/artist/4287d971-d558-4ea7-9384-ee172a102aa0.json and https://artists.proofprofile.net/proofs/artist/4287d971-d558-4ea7-9384-ee172a102aa0.ots, run `ots verify -f record.json proof.ots` (https://opentimestamps.org).