Júlio Cernadas Pereira (13 January 1929 – 11 October 2007), commonly known as Juca, was a Portuguese football midfielder and coach. Most of his career was associated with Sporting CP, as both player a
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 0x1701fe9a6a413f986fbe6321e0cacf16d5526f4b04f2aa50a2d0de1d12f2bfc5. Chain 2 (Bitcoin): anchored in block 954058 (2026-06-17T06:34:31Z). Bridge: the canonical record inside this Bitcoin proof contains the same CopyrightID. Verify: download https://artists.proofprofile.net/proofs/artist/452be1b2-a40d-4fa8-b10d-dd2198d95171.json and https://artists.proofprofile.net/proofs/artist/452be1b2-a40d-4fa8-b10d-dd2198d95171.ots, run `ots verify -f record.json proof.ots` (https://opentimestamps.org).
1. Confirm isrcCode identifies the recording in the pre-2022 source corpus and cc-db-prod record 2. GET OTSVerificationAPI → server-side canonical-record, hash, and attestation checks must pass 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. Confirm CopyrightID is the CopyrightChains transaction hash 5. If all match: the cc-db-prod record is independently anchored on Bitcoin at OTSTimestamp
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0xd4877d0a4e6f6112b25cee5105506822507b1f9f8e0ec820d14ed3be8949313d. Chain 2 (Bitcoin): anchored in block 956856 (2026-07-06T01:25:57Z), registered by our registry partner. The server verifies the private canonical record against OTSHash without exposing internal provider keys. Confirm the public ISRC, CopyrightID, and Bitcoin evidence via https://artists.proofprofile.net/api/v1/bot/ots/verify/track/BR3751900200.
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0x6d40a693c9872dd185802dee6a9e068bc4d75bf55ed18759dca5daad0408878e. Chain 2 (Bitcoin): anchored in block 958907 (2026-07-20T18:35:21Z), registered by our registry partner. The server verifies the private canonical record against OTSHash without exposing internal provider keys. Confirm the public ISRC, CopyrightID, and Bitcoin evidence via https://artists.proofprofile.net/api/v1/bot/ots/verify/track/BRQ8J2000005.