300px|thumb|The Dapper Dans, a barbershop quartet singing in four-part harmony at Walt Disney World Vocal harmony is a style of vocal music in which a consonant note or notes are simultaneously sung
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 0x53b6761469815b4b097aa3932fa7a6604eeb46fe2eaf5cec8a3c937d0ded1e87. Chain 2 (Bitcoin): anchored in block 953630 (2026-06-14T12:06:27Z). Bridge: the canonical record inside this Bitcoin proof contains the same CopyrightID. Verify: download https://artists.proofprofile.net/proofs/artist/3220c213-6266-4f58-acb9-94d8e66f8ac2.json and https://artists.proofprofile.net/proofs/artist/3220c213-6266-4f58-acb9-94d8e66f8ac2.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 0xcb67a95f67414dddd1db68b3632ed5c2023a48d32ada8a57a447890e2fc99bfc. Chain 2 (Bitcoin): anchored in block 956375 (2026-07-02T16:51:38Z), 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/USHM82198300.
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0x3f7155f40070f42db836634533130edbe30a2e0053e2c4614eb7e7751b3b5472. Chain 2 (Bitcoin): anchored in block 958774 (2026-07-19T20:03:27Z), 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/USHM82198301.
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0xcd8ff2993c953b1b7bb516c1236f7aaae5fcca5b75274d5ff7a53e2c2436e5a3. Chain 2 (Bitcoin): anchored in block 956634 (2026-07-04T10:04:33Z), 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/USHM82198303.
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0x8bb2ef71786c95f836852a535f5601fa45e883e91f6c893fbcb5285bb022b838. Chain 2 (Bitcoin): anchored in block 956474 (2026-07-03T08:56:35Z), 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/USHM82198305.
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0x6bc4eb13bd936eac73c995e18bdfc0d4b3b74bcb0381c7b69667c12107aaef4d. 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 via https://artists.proofprofile.net/api/v1/bot/ots/verify/track/ZAQ652401490.
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0x3a7df90468cdf544064c38e7e87867ae04fc8a57acb1cff09c0fae5758ddcca4. 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 via https://artists.proofprofile.net/api/v1/bot/ots/verify/track/ZAQ652401491.
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0xb16a3286ef8881210b6d9d4bede26bf03e29127a4598c75185e0f278e6e275a3. Chain 2 (Bitcoin): anchored in block 956634 (2026-07-04T10:04:33Z), 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/ZAQ652401492.
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0xe4cf761c42354127acd86c58b51212c565879a33cf33ab8ab71b473de1639ba3. Chain 2 (Bitcoin): anchored in block 958316 (2026-07-16T19:42:29Z), 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/ZAQ652401493.
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0x3998872f92683a0187d23d7621fa051f73dd39fbe2ac2f35c66720fe48ccf43d. Chain 2 (Bitcoin): anchored in block 958461 (2026-07-17T23:18:11Z), 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/ZAQ652401494.
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0xdd38bfac839fef97224be78fb091093e2bc549e742b89133a9e5739dfe191551. Chain 2 (Bitcoin): anchored in block 956420 (2026-07-03T00:42:11Z), 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/ZAQ652401495.
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0x89e710785d2ce14a21b36b5f214cca862fd079339ec2b7a21085e0db66cfe200. Chain 2 (Bitcoin): anchored in block 958726 (2026-07-19T11:47:20Z), 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/ZAQ652401496.
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0x1bae9ff449d9acbfb1f401becdf71677e21d46a3357390a0563422a8bc44dbde. Chain 2 (Bitcoin): anchored in block 958716 (2026-07-19T10:15:55Z), 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/ZAQ652401497.
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0x5c87bc00379afa42853e23386463ba47ae7d2283dedae2ef5d622139ebf70609. Chain 2 (Bitcoin): anchored in block 957882 (2026-07-13T16:48:10Z), 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/ZAQ652401498.
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0xdf9bcda54b1bab1f707118e0203ea6e14dcd459fdf61c072583afd0e1874dc5e. Chain 2 (Bitcoin): anchored in block 958627 (2026-07-18T23:33:54Z), 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/ZAQ652401499.
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0x257d588689a8f9b7756c0e69caf6dab138004317be47fd2b71346abf7fa20c24. Chain 2 (Bitcoin): anchored in block 958867 (2026-07-20T11:08:30Z), 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/ZAQ652401500.
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0xc24ef7f96468423ce7ff6d89ba18bd9dfda986cdbb670ac6de6f4fb94bfde507. Chain 2 (Bitcoin): anchored in block 958538 (2026-07-18T10:30:13Z), 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/ZAQ652401502.