thumb|Cacho Tirao (left) Oscar Emilio Tirao (April 5, 1941 – May 30, 2007), known as Cacho Tirao, was an Argentine guitarist. He was a member of the Astor Piazzolla quintet. Biography Tirao was born
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 0x7746d419a6bb57dc94f5e7d6bb5de076bd63d52597f5562455ecd77565ae1d01. 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/c5d03d16-0866-476e-86cd-1816b8485a8d.json and https://artists.proofprofile.net/proofs/artist/c5d03d16-0866-476e-86cd-1816b8485a8d.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 0xeeff465bd6de657a00ca606d3824d19b3baa147fa5803a350e8caa6aefe0e943. Chain 2 (Bitcoin): anchored in block 956440 (2026-07-03T04:03:57Z), 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/ARF107100239.
Música de Buenos Aires, Esto Es... Cacho Tirao
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0x1165b00ff93b3fded2de99257b9599d98481246752c99040dd659c4b024a2738. Chain 2 (Bitcoin): anchored in block 956422 (2026-07-03T01:01:38Z), 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/ARF109901992.
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0x84c232a6c1eb2fc1004458c6299681d837345d2cb417942fcc59fef740aa021e. 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/ARF107900120.
Vals en Do Sostenido Menor,Op. 64, No. 2
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0xda1dad7e8a144f1ece04e18b8cf4127bd9ce93808344d1fa1782f7ff955fa7d2. 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/ARF107900123.
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0x13f2af5d02404cd25d6c5d84206880f4008d2cb466939b7d54a49a179680e36c. Chain 2 (Bitcoin): anchored in block 960266 (2026-07-30T14:44:50Z), 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/ARF100400295.
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0xc62cea26442e9ff5f7ffe8469789b8f36d16aea13e8e11976555784b0a36e207. Chain 2 (Bitcoin): anchored in block 960209 (2026-07-30T05:15:54Z), 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/ARF100400296.
Nocturno en Mi Bemol Mayor, Op. 9, No. 2
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0x7e485f6a19f8ea6238b5ad6e02c5fb2d5cef125325a772493f93ef724257b52d. Chain 2 (Bitcoin): anchored in block 953520 (2026-06-13T13:32:09Z), 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/ARF107900121.
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0xfa92c6936f2da2ef3eb1640aecabc2b82d0576def9f049bc4207aac7b5e1f6fb. Chain 2 (Bitcoin): anchored in block 960138 (2026-07-29T19:35:34Z), 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 via https://artists.proofprofile.net/api/v1/bot/ots/verify/track/ARF109901061.
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0x9e8fce0ba5b4874ee3ad18b8f8edbfc490eea12ed1b06ff46ef096088dff6952. Chain 2 (Bitcoin): anchored in block 957073 (2026-07-07T18:39:05Z), 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 via https://artists.proofprofile.net/api/v1/bot/ots/verify/track/ARF100400298.
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0x532abcf688619f3cd1f339cf721b2b79ea8407fe22d1ea8f5a9578ff85848c50. 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/ARF107900122.
Suite para Orquesta No. 3 en Re Mayor, BWV. 1068: Aria en la Cuerda de Sol
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0x754ce3bad5f56bd4fa5fd060f7b9847c14d1fbb14159f5ae35b51fea6c1628a6. Chain 2 (Bitcoin): anchored in block 956889 (2026-07-06T06:56:49Z), 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/ARF100400297.
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0x1165b00ff93b3fded2de99257b9599d98481246752c99040dd659c4b024a2738. Chain 2 (Bitcoin): anchored in block 956775 (2026-07-05T10:41:06Z), 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/ARF109901992.
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0xc62cea26442e9ff5f7ffe8469789b8f36d16aea13e8e11976555784b0a36e207. Chain 2 (Bitcoin): anchored in block 958749 (2026-07-19T15:48:23Z), 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/ARF100400296.
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0x7904de06cf950b120733717ae1a1684154362105ffc60adf20fb316d2e1d1966. 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/ARF050500340.
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0xea4f239a1b20aa18717dfe0d2a7523c812256349f8ff3bf6a1fb6934d39e576e. 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/ARF050500342.
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0x2da35146266649cdecd181ab4e35c1b2fcad71c5ee4505ffd0af9e024797daab. Chain 2 (Bitcoin): anchored in block 960506 (2026-08-01T03:50:58Z), 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 via https://artists.proofprofile.net/api/v1/bot/ots/verify/track/ARF050500343.
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0xd3afd9cadac42c3182456abc602ec9a8ee8a28edd1cf3e20f6697991300ba03e. Chain 2 (Bitcoin): anchored in block 957120 (2026-07-08T03:22:41Z), 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/ARF050500344.
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0x51b6996e9d998fb0c1ab6883be2fc024559596ba6694c7965d57534ed2404b00. 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/ARF050500345.
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0xe409e16caf2c8883f9a03a284797a5ab9901315cb36f780e0ffa44506baadd0d. Chain 2 (Bitcoin): anchored in block 960240 (2026-07-30T09:57:33Z), 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/ARF050500346.
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0x1ac6a3c0815ec878a76ce1870c57e08ac32c07cce3cdaa7c7b99f89ab4970104. 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/ARF050500347.
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0xd5c858ba17aa47769efa01aa636e23b8e74e77067ad6ccab298c24868e2eb501. Chain 2 (Bitcoin): anchored in block 957120 (2026-07-08T03:22:41Z), 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/ARF050500348.
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0x7a33f9b5c201f863f41d697599136d28ba9ab8e8d4ecf2538ecff656739ea66b. Chain 2 (Bitcoin): anchored in block 957120 (2026-07-08T03:22:41Z), 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/ARF050500349.
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0x77fe360a3e0c6b5f3986cfdb2a4dce6ff7f9c73889c310a54b5c2cd5732b83f5. Chain 2 (Bitcoin): anchored in block 960459 (2026-07-31T20:22:46Z), 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/ARF050500350.
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0x3d269c532dd018a334e91bf5df6eaed43b80e46b004ac4d5bfdb89eeeef9bbf3. Chain 2 (Bitcoin): anchored in block 957120 (2026-07-08T03:22:41Z), 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/ARF050500351.
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0x2f6c22504b8233c6dfe73b114a54478efe61b9f94742e49b1017c48b2e384995. 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 via https://artists.proofprofile.net/api/v1/bot/ots/verify/track/ARF100200905.
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0x531d85f200b682373ae180d7970f7cffe50bd14e174ac6a9af12856d2bfd469a. Chain 2 (Bitcoin): anchored in block 958861 (2026-07-20T10:02:52Z), 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/ARF109901990.
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0x9367e18ac177aa892312af7f3bd2af3f8c8e63d39f5ea081de6bd8e3699ea95a. Chain 2 (Bitcoin): anchored in block 958568 (2026-07-18T15:23:47Z), 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 via https://artists.proofprofile.net/api/v1/bot/ots/verify/track/ARA231100083.
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0xf85f15ba80d7d58566b51cc77351bff10edf389e2fddc27c590310b505b96621. Chain 2 (Bitcoin): anchored in block 957782 (2026-07-13T00:52:48Z), 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/USJE61200116.
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0xda4bb4341a2d57973b102f8a33dac9daf45465f0fe01c8e3412dbe14dab024e2. Chain 2 (Bitcoin): anchored in block 960175 (2026-07-30T00:16:15Z), 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 via https://artists.proofprofile.net/api/v1/bot/ots/verify/track/BXRHI2200061.
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0x51b6996e9d998fb0c1ab6883be2fc024559596ba6694c7965d57534ed2404b00. 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/ARF050500345.
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0xdc8ea4fdd76ddc09dc9d16db19dce4bfa105ce6dd31fd89dc94010d9e29030bc. 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/ARF050800085.