Leonardo Sierra Sepúlveda (born 10 October 1968) is a Venezuelan former road bicycle racer. He competed in the road race at the 1988 Summer Olympics. Career achievements Major results 1988 1st S
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 0x63927ed6b0bff4e2d1ca4d3de9aafa76c3387a82a7d4993cfc4cc387de7fe1d8. Chain 2 (Bitcoin): anchored in block 954066 (2026-06-17T08:11:48Z). Bridge: the canonical record inside this Bitcoin proof contains the same CopyrightID. Verify: download https://artists.proofprofile.net/proofs/artist/7568f2c7-3857-4f13-9937-ecf072e9686d.json and https://artists.proofprofile.net/proofs/artist/7568f2c7-3857-4f13-9937-ecf072e9686d.ots, run `ots verify -f record.json proof.ots` (https://opentimestamps.org).