Mário Sérgio Quaresma Gonçalves Marques (born 25 February 1957) is a Portuguese lawyer and politician, who served as member of the Assembly of the Republic. He was the Regional Secretary of Parliament
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 0x7eca32409b57e429ba547bb98c2aa5ad5455001199c8ac26bdd10c9bdf0802c4. Chain 2 (Bitcoin): anchored in block 954603 (2026-06-20T21:47:54Z). Bridge: the canonical record inside this Bitcoin proof contains the same CopyrightID. Verify: download https://artists.proofprofile.net/proofs/artist/c26ca8cd-93dd-4651-a3a2-bb913b525ab3.json and https://artists.proofprofile.net/proofs/artist/c26ca8cd-93dd-4651-a3a2-bb913b525ab3.ots, run `ots verify -f record.json proof.ots` (https://opentimestamps.org).