Ricardo Francisco Malerba (nickname: Luz Demar) was an Argentine bandoneon player, composer and bandleader (tango musical genre) during the golden age of Argentine tango. Among outstanding compositio
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 0xc8e713cb030c93377248ca728dedab44e4004df061f3050ba8c98e4c231ccbb2. Chain 2 (Bitcoin): anchored in block 953423 (2026-06-12T21:20:00Z). Bridge: the canonical record inside this Bitcoin proof contains the same CopyrightID. Verify: download https://artists.proofprofile.net/proofs/artist/dd6fdfe0-6c08-46ef-af09-60f7fb348fbb.json and https://artists.proofprofile.net/proofs/artist/dd6fdfe0-6c08-46ef-af09-60f7fb348fbb.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 0xd0ef684d41999312dbab07e8cc38b9f32fc2ea899efc6b08571b4fee37d1497b. Chain 2 (Bitcoin): anchored in block 958331 (2026-07-17T00:22:27Z), 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/DEXO52473613.
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0x65318c89f57990d08c5ccc6f1b942ba251fbed8caf2400c8192a1f6593b56c0c. 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/DEXO52473614.
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0xd26a54288d06f8794a628701142bcd2c44135d2a5110afe0c403864d4bc43df0. Chain 2 (Bitcoin): anchored in block 958468 (2026-07-18T00:27:51Z), 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/DEXO52473615.
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0x62dc0098e1ea2de51ff2527fc0e10fc22032a9c45748e24d21c278d1bdfbb40c. Chain 2 (Bitcoin): anchored in block 957546 (2026-07-11T09:35:53Z), 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/DEXO52473628.
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0xdc55af2d6fc8d32eb658d86547ae0f9ccf9f9c11612b2f546c3eb2e62695ed55. Chain 2 (Bitcoin): anchored in block 958447 (2026-07-17T19:47:19Z), 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/DEXN92230453.
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0x3d6ed6d43953bda7e8cc7f59585dc421016ffdf5d5c4186866f34be836fad732. Chain 2 (Bitcoin): anchored in block 958587 (2026-07-18T17:06:26Z), 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/DEXN92230454.
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0x47dfb7965e1edefc050a1700c8c69451de55755959b323a0cef031eaeeba35a9. 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/DEXN92230456.
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0xd3a83f1ca47d4ccaebf85efe281fb932d341be1c449ca0906f2f88d3a754c1c8. Chain 2 (Bitcoin): anchored in block 958992 (2026-07-21T12:58:49Z), 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/DEXN92230471.
La Morena de mi Copla / En Los Jardines de Granada
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0x7f3542724cc23b97464e889ec8f6b47c37a7984757d54d66fbcd81e1af2ed65c. Chain 2 (Bitcoin): anchored in block 956725 (2026-07-05T01:12:41Z), 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/ARA821410721.
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0x53acd284363d48d83d7f378a4891ef650f17819521a074a20c50421cb92c831a. Chain 2 (Bitcoin): anchored in block 958667 (2026-07-19T05:04:54Z), 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/ARA821410726.
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0xa111b0cd49d76ea129632e5372f9ed0750185a204221c4b690c8f40651d35240. Chain 2 (Bitcoin): anchored in block 958756 (2026-07-19T18:57:42Z), 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/USV351473685.
Greatest Tangos Y Valses From Argentina To The World
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0xecbafee72ee4199e82aabff5162ef753f9928ba61fad4e18e31fbae0d7921a3b. Chain 2 (Bitcoin): anchored in block 957118 (2026-07-08T03:20:19Z), 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/ARF044300007.
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0x9a981c5d3b7a57dedb33fac347e8b8fb03356e7887a43766c6f03b067f2656b8. Chain 2 (Bitcoin): anchored in block 957145 (2026-07-08T08:56:20Z), 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/CA5KR1551924.
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0x33fc912af57d8b7fafe28f2dd503783a1dd3cdb2c8b2e7a241ce5eb5ac053b5f. Chain 2 (Bitcoin): anchored in block 953528 (2026-06-13T15:41:10Z), 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/CA5KR1551927.
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0x45a6ea324c3eae6abbb98888466307c4e261fb401835809872f3f34219780faf. Chain 2 (Bitcoin): anchored in block 957145 (2026-07-08T08:56:20Z), 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/CA5KR1551938.
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0x2fafcf4ce63eb4c8de29fe824b920c47279817f675efe9448138ea13728b84f1. Chain 2 (Bitcoin): anchored in block 960111 (2026-07-29T13:21:01Z), 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/CA5KR1551933.
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 0x80f46ff8a36fba816e98c6f19a6a6ac01f18114d317a302042b262fc6544c106. Chain 2 (Bitcoin): anchored in block 960503 (2026-08-01T03:41:24Z), 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/CA5KR1551934.