Castanheiro (Portuguese meaning the chestnut tree) may refer to the following places in Portugal: Castanheiro, a civil parish in the municipality of Carrazeda de Ansiães Castanheiro do Sul, a civil
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 0xcc3b9956675d6e012a524dbd8b3cf8f875173e8dcad2c2ea433299142039c28e. 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/75d8f652-d6d5-4634-adb7-890b5effa294.json and https://artists.proofprofile.net/proofs/artist/75d8f652-d6d5-4634-adb7-890b5effa294.ots, run `ots verify -f record.json proof.ots` (https://opentimestamps.org).
Os Pobres Têm Voz: O Canto das Comunidades, Vol. 2