César Muñoz Vicuña (1929–2000) was an Ecuadorian chess master. An amateur, he was an engineer by profession. He played for Ecuador at first board in the fourth World Student Team Chess Championship
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 0x99d849a3a8b2ea13dab3ce5350d8d9621e5c5d1b85eb7526f0399dce00c603ac. 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/ce9a321d-a866-4ec9-b723-d7a436be42d8.json and https://artists.proofprofile.net/proofs/artist/ce9a321d-a866-4ec9-b723-d7a436be42d8.ots, the client at https://opentimestamps.org runs `ots verify -f record.json proof.ots`.