Santiago de Cali (), or Cali, is the capital of the Valle del Cauca department, and the most populous city in southwest Colombia, with an estimated 2,280,522 residents in 2023. The city spans with o
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 0x0bdebc15580cb2ec70997a5f7b15e41159c49fab884d1c8280fe2825e6c717d2. Chain 2 (Bitcoin): anchored in block 953625 (2026-06-14T11:37:06Z). Bridge: the canonical record inside this Bitcoin proof contains the same CopyrightID. Verify: download https://artists.proofprofile.net/proofs/artist/23582a0a-820d-42e2-9b02-45460b3e7306.json and https://artists.proofprofile.net/proofs/artist/23582a0a-820d-42e2-9b02-45460b3e7306.ots, run `ots verify -f record.json proof.ots` (https://opentimestamps.org).