Old Havana () is the city-center (downtown) and one of the 15 municipalities (or boroughs) forming Havana, Cuba. It has the second highest population density in the city and contains the core of the 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
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0xf1c52ebf5b1d46807f941b905871cf0b92c5454c0e7eb52b2e3af7758771b53f. 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/757d3811-8498-4cb5-a4a1-81c1063c335f.json and https://artists.proofprofile.net/proofs/artist/757d3811-8498-4cb5-a4a1-81c1063c335f.ots, run `ots verify -f record.json proof.ots` (https://opentimestamps.org).