The musical term alto, meaning "high" in Italian (from Latin: altus), historically refers to the contrapuntal part higher than the tenor and its associated vocal range. In four-part voice leading alto
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 0xb397f615284e04160b6467c6a1d2e5644563820a7c44c28b542a8fcb21cbf69e. 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/0f49ac7d-ce97-4bcb-8722-2740aa5bd3d3.json and https://artists.proofprofile.net/proofs/artist/0f49ac7d-ce97-4bcb-8722-2740aa5bd3d3.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 0x155867db0df044e8add1659eb76263c5817cb5a0e61ba89754aafef5f9751d79. Chain 2 (Bitcoin): anchored in block 958846 (2026-07-20T10:35:07Z), 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/US3DF2298785.
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0xdc67217afc67edc426b196c0ade71055826b87b417b47578f49e9ac6ccdf14b3. Chain 2 (Bitcoin): anchored in block 958917 (2026-07-20T17:53:56Z), 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/NLX9G2200281.
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0xcedabbd928d59ed87e55ae89f96d81144960d7ca148c91ec0023abe3019e9ed6. Chain 2 (Bitcoin): anchored in block 959058 (2026-07-21T21:09:36Z), 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/US3DF2447481.
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0xacd02168812406052e2f26e2237fa65b16e5ccc3113c34a36336cfe93f296bb0. Chain 2 (Bitcoin): anchored in block 958561 (2026-07-18T14:22:01Z), 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 via https://artists.proofprofile.net/api/v1/bot/ots/verify/track/US3DF2457538.
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0xb264506feae0ca5458be5a0eb85ea4c1725d6408916815a18d3a53a4003f0c1a. Chain 2 (Bitcoin): anchored in block 956822 (2026-07-05T18:48:28Z), 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/USANG2404829.
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0x6aea064044bdb638210ee92e3265692a4da49017a1babad2e0d42f97c8f4088b. 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/QM3DF2421499.
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0x89d91f226f18e0fdd3ce6a6d7d44f539a94188ed6ba251c292495f813414969d. Chain 2 (Bitcoin): anchored in block 958383 (2026-07-17T08:20:01Z), 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 via https://artists.proofprofile.net/api/v1/bot/ots/verify/track/QM3DF2421623.
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0x46bbaf948cf901560d346382db8541fbb7af28e5bf83dc38ce20e387c47a0de4. Chain 2 (Bitcoin): anchored in block 958228 (2026-07-16T05:45:10Z), 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/USANG2495970.
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0xfb4ec2dcbe5d51b8c8a46ab18c96f5b95b52108ff18bb08f383d37ec0f848180. Chain 2 (Bitcoin): anchored in block 958788 (2026-07-19T22:07:06Z), 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/CH7812530888.
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0xf03eb36f409e252b66832ea49f2e45bd5972d59dc09255c4a0d930c76a7b924b. 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/US3DF2568865.
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0x237b9e75b381a49d39e3fdba7ac667930d9bbda4229c478b019ca87cfc670687. 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/USANG2426990.
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0x062f5bd93963105f0265174eb09711dfd450a10ca0ee8d15b293fe565cef47ba. 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/UKZGC2307392.
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0x098d20170b33c419a5227452b355dcf45082bee5070a90c624408ac0408490ac. Chain 2 (Bitcoin): anchored in block 959152 (2026-07-22T19:00:35Z), 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/USANG2426991.
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0xa531f76355e7c8adecf5313f6d8cc7747138ed641158e84e2dcb144cb92b1e31. 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/UKZGC2401979.
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0xd52e79370d3bde83dc9df170d0a71d7fc35d972cb6767119cc74f3a2bd062c62. 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/US3DF2494204.
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0x58c48f7af462cf2972394a474e5fc015d37c65c5b0ca147905c63af1f457601f. 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/US3DF2494205.
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0x0c44de9c7b3c6a8a9ec7562fdf0b8f6b7fd60c4eb7343da1cb604dcb8659831f. 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/UKZGC2408335.
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0xe5f6f5372966bf30f5acf95d84b17b84ad99df3f9a597f927836962c754bcfeb. 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/US3DF2450603.