Vocal Spectrum is a barbershop quartet from St. Charles, Missouri. In 2004, Vocal Spectrum won the Barbershop Harmony Society's International Collegiate Quartet Contest, and on July 8, 2006, they beca
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 0x3a8370d07bbbbb65cf8374913240ca4d78c8f2a92f603a35722e09b1b9f6acac. 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/992ba0cd-5b41-44df-9825-bc077318e37e.json and https://artists.proofprofile.net/proofs/artist/992ba0cd-5b41-44df-9825-bc077318e37e.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 0xc1910c2333695f4ec00e388b07493b7c8ba04ea35370c0689f442d4f93fd3ce2. 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/US29H1700301.
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0x53f19f53b7d909f28712be8aa54b1cf184eb9a4d37bf4280fe55d57a6ab394b4. Chain 2 (Bitcoin): anchored in block 959159 (2026-07-22T17:48:40Z), 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/US29H1700302.
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0x8c7ead0494dd166ca40fef6bf3e2450218a392fc1516d8963325b789a98e1086. 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/US29H1700304.
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0x55ea880ba016fe765e802c59b43752e61c7fb182c8fa41f78eafdd2c3645cd09. 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/US29H1700306.
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0x9afecfc221b22287951f80c51ab0afc2152fb5bef064e71ff3a0b45c054a5932. 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/US29H1700309.
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0xe69418a79594f89b3acf02c0977efe5e2f813e88977ce4dd23d51592c5291f81. 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/US29H1500556.
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0x0f5d522a3e03649afc759565cba51487e58cd291699d5ce38488cc4ffa8018bc. 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/US29H1100438.
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0xcc7eb85083963087c9deaaa7b2d5133fd8574ac074fd58733d39388a1d3e0941. 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/US29H1100440.
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0x59d1ba2184f5955d42aaf253d7139694f6955e88fc83ba831448e85a9adb0274. 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/US29H1100442.
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0x62e65fb26353302fee5b69cdf3aeb2ce3980c05f7b5f60a59240b318262f5b7b. 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/US29H1100445.
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0xf3f7828464c062db238149b29e1539e9e2a1f8fba989f8c5a4bd76810dd79325. 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/US29H1100446.
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0x72719cc840c36beec55b0808e4dbf7fb1c7916da2a07331c325c2aef1040bcf2. 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/US29H1100449.
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0xd6a1e2159443ae68ddb5bdc3490592855cba16620cbd8018e1f9db78bf0a132a. 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/US29H0810759.
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0x1942933778ad39e0d3a5e6288787eb15386d4022932bbf50f4bf1fc1cd89183e. 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/US29H0810760.
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0x3e646cc5550b6014c1ad575bef7b21392a9b20ec7526a8a8d6e3552409afb04f. 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/US29H0810761.
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0x17d1205a314829b3b9bc535f688b40428ece3155f4ffc6677a121afb1026eb14. Chain 2 (Bitcoin): anchored in block 959163 (2026-07-22T20:49:34Z), 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/US29H0810762.
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0x90bac5c8c252daf9a0efe8af8b4697d0dfd4563bfb08fd6a628d42b4c0f87c75. 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/US29H0810763.
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0xf5bfc4fe6817c3025b7be3688832d2049d5ca8511d14656b3ce01562957f6b8b. 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/US29H0810769.
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0xaf2c45bba3b12985dd15471331c3d4b725ab85ee0c34f1dfdc0f5f8340d209a0. 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/US29H0810770.
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0x0ae9e0ef455d931163a57f0d1876aadaed6d3f727fec9379aef0e22730162c7a. Chain 2 (Bitcoin): anchored in block 959159 (2026-07-22T17:48:40Z), 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/US29H0810747.
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0x26488ab76ed94602b56337678a55a202b9e9ed40c91ae7198bc76f994781b03d. 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/US29H0810750.
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0xcd1639b404fb581076a35a7f1820e7403fec139d00c5b251a7f1d3ed3b490f7b. 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/US29H0810751.
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0x6c5b29dc5d9973c5bad38edad30f4e45cc65cd77316787f6087562133113fd5e. 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/US29H0810755.
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0x5f91255db261683172a88d76412e110bd73a88abd3730cecb0dd885e06c95802. 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/US29H0810756.
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0x26659dd7ff2d607919718b2c109e94542c4b4bb3bd55bf9270ddc4d63ff7641b. 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/US29H0810757.
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0xc841ec6a4d79812f050a982210785fe01d3da80bc164fc451c4915c13fdd56b6. 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/TCAGW2394768.
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0x3f864c3ba278da781f8879dc88cff8cead78fb88d37f44479320b34ef34b8e8a. 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/TCAGW2394783.
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0xc58e12426624f46c788660ae0dcd89344762d15cd118dd6aebcda5b84787c195. 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/TCAGW2394786.
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0xd31d684c30d7eee77f7aa33aa513ec8d39ef4523a2cfa39dda64d7f6f78fe621. 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/TCAGW2394787.
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0x5c0e1fd3ea13cb51d8d1963a44fdad9ec3d7eefe14ce811bc29efad5925882b0. 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/SE39E1300101.
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0xa963c6de54a941e013e0c5bcb71b1679ba0888742ba71a8738086ac62c5ed37b. 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/SE39E1300102.
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0x8708db91d01b15af1a697931aade7d9aa44aaab4e1bf236fb52b18fd6e00c612. 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/SE39E1300103.
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0x3b51a62d3229023fb83fb2a2926cf3f777d368d70e012a9f47a4d2f91cae97b7. 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/SE39E1300104.
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0x3cc4c912de0069dc606fc75e1392cafe57c700a17782bf3986777c66fe1c7473. 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/SE39E1300109.