Chiasso (; ) is a municipality in the district of Mendrisio in the canton of Ticino in Switzerland. As the southernmost of Switzerland's municipalities, Chiasso is on the border with Italy, in front
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 0xe72e65e63397ae5aeef5eaf6975066d2bda64094710aba917c1175880f333aa2. 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/5eb672e7-5026-4c07-a000-d8d1fb558732.json and https://artists.proofprofile.net/proofs/artist/5eb672e7-5026-4c07-a000-d8d1fb558732.ots, run `ots verify -f record.json proof.ots` (https://opentimestamps.org).