Rubén Juárez (5 November 1947 – 31 May 2010) was an Argentine bandoneonist and singer-songwriter of tango. Early life He was born in Ballesteros, in the province of Córdoba on 5 November 1947 and
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 0xc488fd4b40400515d5c58612fecaaf3e9152a08a32d4ab258ebc5d62379eead5. 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/ac38d512-eb19-4f5e-97dd-d1c0781f7095.json and https://artists.proofprofile.net/proofs/artist/ac38d512-eb19-4f5e-97dd-d1c0781f7095.ots, the client at https://opentimestamps.org runs `ots verify -f record.json proof.ots`.
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 0x465973647ce6d3d0e7fdc008035da11cf325bc4dd5b15816b3c522b54d2f19ab. Chain 2 (Bitcoin): anchored in block 958913 (2026-07-20T16:58:47Z), 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 at https://artists.proofprofile.net/api/v1/bot/ots/verify/track/ARF047200005 — a six-check JSON result.
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0x6f3eed7f490c421f169b829f70927d898c8b97ee25e28d397f521e9361cc89e8. Chain 2 (Bitcoin): anchored in block 958985 (2026-07-21T08:39:15Z), 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 at https://artists.proofprofile.net/api/v1/bot/ots/verify/track/ARF049600469 — a six-check JSON result.
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0xb69aa2a5e93bcbc9942705ead3d36a26e302f67a7d80e3d6258a6dba751370aa. 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 at https://artists.proofprofile.net/api/v1/bot/ots/verify/track/ARF049500851 — a six-check JSON result.
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0x34e68491cf37188e7ec8a580c7c13192942b27458e6a2fd2b2629279a548ed88. Chain 2 (Bitcoin): anchored in block 958104 (2026-07-15T05:34:05Z), 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 at https://artists.proofprofile.net/api/v1/bot/ots/verify/track/ARF049500861 — a six-check JSON result.
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0x5b3e69c44bd2d715a2184b4a3aefc48f3fae5bd97af638e17b9a363338b6e104. Chain 2 (Bitcoin): anchored in block 959118 (2026-07-22T10:01:58Z), 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 at https://artists.proofprofile.net/api/v1/bot/ots/verify/track/ARF047700007 — a six-check JSON result.
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0xa6c774b3a26d5b6a0a3417dea677b400d13fb0dd98936f27dab69f767127deb6. Chain 2 (Bitcoin): anchored in block 958224 (2026-07-16T02:28:43Z), 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 at https://artists.proofprofile.net/api/v1/bot/ots/verify/track/ARF048700014 — a six-check JSON result.
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0x465973647ce6d3d0e7fdc008035da11cf325bc4dd5b15816b3c522b54d2f19ab. Chain 2 (Bitcoin): anchored in block 959043 (2026-07-21T18:40:26Z), 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 at https://artists.proofprofile.net/api/v1/bot/ots/verify/track/ARF047200005 — a six-check JSON result.
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0x13200b9ce2b0177950c30030fca0ef91e94832202f18f8015114c81b454b1cd1. Chain 2 (Bitcoin): anchored in block 958931 (2026-07-20T21:15:01Z), 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 at https://artists.proofprofile.net/api/v1/bot/ots/verify/track/ARF049601304 — a six-check JSON result.
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0xa7d1968c9b5e0d4435be88e1e30cfbd3ed1d87bf5872b05952e5e1f9d26644fb. Chain 2 (Bitcoin): anchored in block 958137 (2026-07-15T09:47:57Z), 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 at https://artists.proofprofile.net/api/v1/bot/ots/verify/track/ARA590700858 — a six-check JSON result.
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0x3f1fd0cd2dcd15d78b2f3fd4011992577e5a1c0308661382ea735c775cb4ca6c. Chain 2 (Bitcoin): anchored in block 956826 (2026-07-05T19:27:56Z), 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 at https://artists.proofprofile.net/api/v1/bot/ots/verify/track/ARA590700859 — a six-check JSON result.
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0x7f93ab0307226469ba0c10ff7b98c7021028e23c38ccec3379d9a168febfd717. Chain 2 (Bitcoin): anchored in block 958742 (2026-07-19T14:09:34Z), 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 at https://artists.proofprofile.net/api/v1/bot/ots/verify/track/ARA590700861 — a six-check JSON result.
Buenos Aires, Días y Noches de Tango: Sábado / Bohemia
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0x2c6554e093beaeda5ca0c75a6cd66aae9d2ec4d1b47b46828b38b6d1eebf3e38. Chain 2 (Bitcoin): anchored in block 958690 (2026-07-19T07:14:39Z), 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 at https://artists.proofprofile.net/api/v1/bot/ots/verify/track/ARD191900149 — a six-check JSON result.
Don Carlos De Buenos Aires (Remastered 2025)
La Cancion De Buenos Aires (Remastered 2025)
El Tango Es Tango Con Rubén Júarez (Remastered 2025)
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0xeadb04e5c5c8b9fd9a455cf919671e7fab2efe5289449add943e4bb6219c78f6. Chain 2 (Bitcoin): anchored in block 960207 (2026-07-30T04:47:22Z), 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 at https://artists.proofprofile.net/api/v1/bot/ots/verify/track/ARG601013568 — a six-check JSON result.
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0xd66b58f32d50db1534d1849c1ca6ef4c7850a51781b2239e059a44988f467ca1. Chain 2 (Bitcoin): anchored in block 960095 (2026-07-29T11:07:37Z), 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 at https://artists.proofprofile.net/api/v1/bot/ots/verify/track/ARF059900557 — a six-check JSON result.
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0xc4390a0add1b4939c574ce719294cb6d7aaa910e9cd362bb11804802f37c597e. 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 at https://artists.proofprofile.net/api/v1/bot/ots/verify/track/US3DF2029536 — a six-check JSON result.