SI is the International System of Units. SI, Si, or si may also refer to: Arts, entertainment, and media Literature Si (novel), a 2014 novel by Bob Ong Sí (Peruvian magazine), a magazine notable
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 0x53142912b7f784fa6ff44d3589c5acc6338d79d696930b3f7fe9b00eeed7a06a. 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/5ad1e1d0-ab45-4c6f-bbf2-229f13fbd15f.json and https://artists.proofprofile.net/proofs/artist/5ad1e1d0-ab45-4c6f-bbf2-229f13fbd15f.ots, run `ots verify -f record.json proof.ots` (https://opentimestamps.org).