Marcelo Mendonça de Mattos or simply Marcelo Mattos (born 10 February 1984) is a Brazilian former football defensive midfielder. He is known for his positioning, tight marking of the opposing player
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 0x1680c895e6221d7282a72552eaca96568e0512faf145031b4610d199ec78526e. Chain 2 (Bitcoin): anchored in block 954638 (2026-06-21T03:45:44Z). Bridge: the canonical record inside this Bitcoin proof contains the same CopyrightID. Verify: download https://artists.proofprofile.net/proofs/artist/d3150eea-5c0b-49eb-b2cf-c2c0dd4f3828.json and https://artists.proofprofile.net/proofs/artist/d3150eea-5c0b-49eb-b2cf-c2c0dd4f3828.ots, the client at https://opentimestamps.org runs `ots verify -f record.json proof.ots`.