Duo Ouro Negro (also known as The Black Gold) was a kwela music group consisting of Raúl Indipwo and Milo MacMahon, formed in 1959. The music group was first a trio, but when Jose Alves Monteiro left,
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 0xc18c6810f13fba75cb7f49575fc71117a0098bb8c1a2c97d9d5523bd07a8eb8b. Chain 2 (Bitcoin): anchored in block 953625 (2026-06-14T11:37:06Z). Bridge: the canonical record inside this Bitcoin proof contains the same CopyrightID. Verify: download https://artists.proofprofile.net/proofs/artist/29783188-ee53-47c1-9e36-3313bc082684.json and https://artists.proofprofile.net/proofs/artist/29783188-ee53-47c1-9e36-3313bc082684.ots, run `ots verify -f record.json proof.ots` (https://opentimestamps.org).
Livro sem Fim (Grande Prémio TV da Canção Portuguesa 1967)
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 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 0xdca72b5bdaae7cb5eb9ac52647dcb9aed47f2fc544a5a1c64c0ce4e94d68e027. Chain 2 (Bitcoin): anchored in block 956634 (2026-07-04T10:04:33Z), 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/PTVC16000023.
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0x4175fc01456b3981d852a0b625e899f9a448907f830f713b69da85ac0e1b1cf6. Chain 2 (Bitcoin): anchored in block 958256 (2026-07-16T07:22:18Z), 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/PTVC11000064.
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0xa8dff4a9cb6d3980335ff1b3e557d6f829a362c25b63bbb9992b481a20c094fe. Chain 2 (Bitcoin): anchored in block 956822 (2026-07-05T18:48:28Z), 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/PTVC11000069.
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0x3c6c9491f56bb26584cb722889541a4b7eb95625ae4c054768eab30600ebbc65. Chain 2 (Bitcoin): anchored in block 958238 (2026-07-16T04:30:31Z), 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/PTVC11000072.
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0x1f35d6e4eeae435fb03019d141d7829dba3dfda599dddaa9922b64201a348514. Chain 2 (Bitcoin): anchored in block 958340 (2026-07-17T00:53:26Z), 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/PTVC11000073.
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0x66a547715b5ed3ace66ed31fc3ee6b472f0df523f83ef19e87c4239deebb8ed8. Chain 2 (Bitcoin): anchored in block 958783 (2026-07-19T21:20:45Z), 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/PTVC11000090.
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0xbacfd6e7a553671155e751369c80474ab25e03d67ac90fa660d3dbeb6bf31183. Chain 2 (Bitcoin): anchored in block 960117 (2026-07-29T14:28:24Z), 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/PTVC16600173.
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0x89cd5770ab6f083e4b7efddbb18326132878e3d1f64ba3ae3324438864d3ea1f. Chain 2 (Bitcoin): anchored in block 960441 (2026-07-31T17:29:52Z), 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/PTVC16600179.
Portugal Deluxe Volume 1: Um Cocktail Estereofónico
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0x2499eda24d385bc53cd5c3866979e1fac086a4475066fe1d5ca175e0048b350f. Chain 2 (Bitcoin): anchored in block 960370 (2026-07-31T08:38:45Z), 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/PTVC16500046.