Mario Cassi (born 6 December 1973) is an Italian baritone. Career Born in Arezzo, graduated in economics at University of Florence, Cassi studied singing privately first with Slavska Taskova Paolet
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 0xce459c317843119cb9c3b8821535dd4ad4b340cc22ef880e51e0ad802723dd37. Chain 2 (Bitcoin): anchored in block 954065 (2026-06-17T08:10:43Z). Bridge: the canonical record inside this Bitcoin proof contains the same CopyrightID. Verify: download https://artists.proofprofile.net/proofs/artist/448111d1-45fc-4f7c-9a3e-0835aeb62faf.json and https://artists.proofprofile.net/proofs/artist/448111d1-45fc-4f7c-9a3e-0835aeb62faf.ots, run `ots verify -f record.json proof.ots` (https://opentimestamps.org).