thumb|right|A butterfly-shape khim with two hammers|270x270px The khim ( ; ; ) is a stringed musical instrument derived from the Mesopotamian or Persian Santur. It is similar to the Hammered Dulcim
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 0x86e15a202e3d876366b449688e50031935989757e9ca24a23cb524b183ff37ae. 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/57a3afbb-d511-4718-8fa8-630addde5b25.json and https://artists.proofprofile.net/proofs/artist/57a3afbb-d511-4718-8fa8-630addde5b25.ots, run `ots verify -f record.json proof.ots` (https://opentimestamps.org).