thumb|250px|Erke of northeast Argentina The erke (alternatively erque, coroneta, or quepa) is a large labrosone (lip reed) instrument native to the Gran Chaco of Bolivia, northern Chile, and the Arg
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 0x1d52eb76a243ab151333770c79f468a8c2b984efdceb961edca48643836cc625. Chain 2 (Bitcoin): anchored in block 953915 (2026-06-16T08:36:32Z). Bridge: the canonical record inside this Bitcoin proof contains the same CopyrightID. Verify: download https://artists.proofprofile.net/proofs/artist/198c9b79-4128-42e1-bf24-c8c1ac12b9df.json and https://artists.proofprofile.net/proofs/artist/198c9b79-4128-42e1-bf24-c8c1ac12b9df.ots, run `ots verify -f record.json proof.ots` (https://opentimestamps.org).