Osvaldo Fresedo (May 5, 1897 - November 18, 1984), nicknamed El pibe de La Paternal ("the kid from La Paternal") was an Argentine songwriter and director of a tango orchestra. He had one of the longe
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 0x4096eda756c72891a2f76e66be05dc5186ab77823c618877d08738ff66238940. Chain 2 (Bitcoin): anchored in block 953407 (2026-06-12T19:24:56Z). Bridge: the canonical record inside this Bitcoin proof contains the same CopyrightID. Verify: download https://artists.proofprofile.net/proofs/artist/a3dbe7b0-361a-478e-87b8-1712b22d68b4.json and https://artists.proofprofile.net/proofs/artist/a3dbe7b0-361a-478e-87b8-1712b22d68b4.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 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 0x85e40b69a3837fcfaaec166c70da33a5f4caaef2c2701e9f5b72d4e9f81003a4. 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/QMEU31506358.
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0x4170aa7da09cf35104551be8ca582f801e8c7af934a9df2ded614563edddd98b. Chain 2 (Bitcoin): anchored in block 953515 (2026-06-13T12:53:06Z), 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/QMEU31506362.
Tangos del Ayer y del Hoy - Pasión y Melancolía de Osvaldo Fresedo
El Pibe De La Paternal - Osvaldo Fresedo Early Tangos
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0x8351de5cc9a66aed8f57459dcea4b670eb428f1faf7244b9006c1057ccb747c2. Chain 2 (Bitcoin): anchored in block 956304 (2026-07-02T03:55:08Z), 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/DEXO32076130.
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0xc4c3e3e499fb1047021e5adb0518fe0e1c5363a8df0eb0ac7c28b9194eaef138. Chain 2 (Bitcoin): anchored in block 957819 (2026-07-13T07:53:33Z), 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/DEXO32076131.
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0xdcbdeaba36fd1bfd228ba96288c7a64907eb8b096fd6da1bf66a8f8412aa4933. Chain 2 (Bitcoin): anchored in block 956304 (2026-07-02T03:55:08Z), 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/CA5KR1846963.
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0xfdcaf8d87520652e4452b1546971273df5ad68b52a136ad3a63471c32658befe. Chain 2 (Bitcoin): anchored in block 956302 (2026-07-02T03:30:09Z), 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/CA5KR1846964.
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0xe30b9e19746d36c8c89548afe58be134b772606190f9b4c62f97480e211228d0. Chain 2 (Bitcoin): anchored in block 956304 (2026-07-02T03:55:08Z), 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/CA5KR1846975.
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0xe7f6f50221e00c54b7c8b6d59330004e34d890294597904186b7eee001424062. Chain 2 (Bitcoin): anchored in block 956302 (2026-07-02T03:30:09Z), 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/ES6601600120.
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0x94eb3ed04c34bc2d39a9c20696bae3c926b25eaabf3fedbfba7e5a6c71ac00fc. Chain 2 (Bitcoin): anchored in block 959128 (2026-07-22T12:33:25Z), 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/ARA821550617.
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0x9dc8ab1944015cba7b709ad7ba192933af99d0ddd441a2a2e35615272e6c54d8. Chain 2 (Bitcoin): anchored in block 956302 (2026-07-02T03:30:09Z), 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/ARA821550628.
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0xffc7a6c42b989a6371e2ac97974996a573d0728bab071a9410288f850853a006. Chain 2 (Bitcoin): anchored in block 959152 (2026-07-22T19:01:39Z), 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/QM6MZ1540248.
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0x8cf7d2c5845156d7d55a9fe9fb19a695183f21dbcfe54e499ed61c3ad2204702. Chain 2 (Bitcoin): anchored in block 957819 (2026-07-13T07:53:33Z), 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/QM6MZ1540253.
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0xb9dceb4a7e421d3a4ebed36eb5c3af544662e3bd42799f1ade1eeca162eedb3c. Chain 2 (Bitcoin): anchored in block 959144 (2026-07-22T15:38:35Z), 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/QM6MZ1540257.
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0xa1fc8c2f3b89a3df50e227947e266d53a9ce1f038a5259c0db5faae4bf7a3a23. Chain 2 (Bitcoin): anchored in block 959159 (2026-07-22T20:18:50Z), 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/QM6MZ1540259.
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0xfcbcd7b505c3be1b129827d4c48bec6174c78b255374dcc46a906cc5b620dadb. Chain 2 (Bitcoin): anchored in block 956304 (2026-07-02T03:55:08Z), 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/QM6MZ1540267.
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0xae6d94d86aabc38286cb7f3359943b2f49c6786abf4aba61ec903081762dddee. Chain 2 (Bitcoin): anchored in block 956304 (2026-07-02T03:55:08Z), 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/QM6MZ1540268.
Tango Classics 338: Felicia (Historical Recordings)
Tango Classics 337: A la Deriva (Historical Recordings)
Tango Classics 336: Fui Testigo (Historical Recordings)
Tango Classics 335: Preparense (Historical Recordings)
Tango Classics 334: En Mis Noches (Historical Recordings)
Alfredo de Angelis vs. Osvaldo Fresedo, Tango