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 0x87138409882ca7f77d6bdcf7bd3381e8615eb962f6aa6e0da527be475601d195. 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/06f7e279-0440-4b53-a34b-a720a01cf388.json and https://artists.proofprofile.net/proofs/artist/06f7e279-0440-4b53-a34b-a720a01cf388.ots, run `ots verify -f record.json proof.ots` (https://opentimestamps.org).
Mozart: Clarinet Quintet in A Major - Schubert: String Quintet in C Major
Mozart, Schubert, Ravel and Janácek: Chamber Music Selections
Introduction and Allegro for String Quartet, Flute, Clarinet and Harp, M. 46
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 0x507cd43469e154a115eadce06b7dcc3a94da685fd548d8b33b7c178d5bf99af0. 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/USZDG0601876.
Quintet in A Major for Clarinet and Strings, K. 581: I. Allegro
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0xe876a7b17d4361e0313a263beca921376ad92678c3f980e92fa7bcb8aebaf64c. 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/USZDG0601140.
Quintet in A Major for Clarinet and Strings, K. 581: II. Larghetto
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0xbe0441e337c8a9ca2d17a2a6d8a2bf8a24606573f2c552da5064192352b662d3. Chain 2 (Bitcoin): anchored in block 953513 (2026-06-13T12:47:07Z), 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/USZDG0601141.
Quintet in A Major for Clarinet and Strings, K. 581: III. Menuetto - Trio 1 - Trio 2
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0xd809f9f8e249babc1c116e3c6646030ecff58ac1005d2cb6f4d8d9366e14efda. 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/USZDG0601142.
Quintet in A Major for Clarinet and Strings, K. 581: IV. Allegretto con variazioni
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0x0936a03d5bedc5fbcaffe56be7597cdd35ff40f9e38948d9bacbe5bf15de27ff. Chain 2 (Bitcoin): anchored in block 960183 (2026-07-30T01:10:20Z), 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/USZDG0601143.
String Quintet in C Major, D. 956: I. Allegro ma non troppo
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0x3a2b982b7b7c5f0ebcb96e2c51bbb47aef87b303b5e0e9db86fe757161167c05. 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/USZDG0601984.
String Quintet in C Major, D. 956: II. Adagio
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0x2000c2c8b34befec43e91141daf3244ad7afea0fc3eb91a07584c7a1d08be4d6. Chain 2 (Bitcoin): anchored in block 960276 (2026-07-30T16:01:17Z), 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/USZDG0601985.
String Quintet in C Major, D. 956: III. Scherzo - Trio
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0xee94dbb9395f00b10ae56c4fb7e9bfe364e1849b25e651e10fee377cd5394749. Chain 2 (Bitcoin): anchored in block 960379 (2026-07-31T09:25:34Z), 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/USZDG0601986.
String Quintet in C Major, D. 956: IV. Allegretto
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0x66714b8fa5ad45467982760f2b4d9afca8ec43992691df35dcf24dfebc22e0cc. Chain 2 (Bitcoin): anchored in block 960348 (2026-07-31T05:17:02Z), 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/USZDG0601987.
Quartet in F Major for Oboe, Violin, Viola and Cello, K. 370: I. Allegro
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0x5d79f17b7c72adaf191c55c34efe1ccb65174ea6365ef0e5a4100ffeeac53c13. 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/USZDG0602417.
Quartet in F Major for Oboe, Violin, Viola and Cello, K. 370: II. Adagio
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0x8a7d58cb958a7821e56c17e5e2db81328431ce6df1a1a547b8d60fba61411024. 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/USZDG0602418.
Quartet in F Major for Oboe, Violin, Viola and Cello, K. 370: III. Rondeau: Allegro
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0xcb673ea793ccee40b025247f6a52d9285b804bd45f8f6a30a047f4b612dc3d05. 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/USZDG0602419.
String Quartet No. 1, JW 7/8, "Kreutzer Sonata": I. Adagio - Con moto
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0x092ce8d19219a746c560c1762adcef25d3d7b990e6438b0d536772654dc08eaf. Chain 2 (Bitcoin): anchored in block 960273 (2026-07-30T15:42:38Z), 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/SEWDL0561205.
String Quartet No. 1, JW 7/8, "Kreutzer Sonata": II. Con moto
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0x7306320f8680afd7e9d35c4250b7bde262eed54697e19254e1df01f71ffe4948. Chain 2 (Bitcoin): anchored in block 960455 (2026-07-31T19:53:13Z), 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/SEWDL0561206.
String Quartet No. 1, JW 7/8, "Kreutzer Sonata": III. Con moto - Vivo - Andante
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0xfa0cc8dd389822da1d1b2094cf8bd58554a9d9c7bb1727579620e5642749c77b. 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/SEWDL0561207.
String Quartet No. 1, JW 7/8, "Kreutzer Sonata": IV. Con moto - Adagio
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0x0ea2298e295737fccf74c47d5b36cdfa32839abf5df324fd860384b64c8d25dc. 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/SEWDL0561208.
Quintet in E-Flat Major for Horn, Violin, Two Violas and Cello, K. 407: I. Allegro moderato
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0x873e1b901f8050c124edc2fcd0ef2386ed1ecf165d9da5277291f6715e4c3162. 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/USZDG0602420.
Quintet in E-Flat Major for Horn, Violin, Two Violas and Cello, K. 407: II. Andante
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0xdb4ac8efae530eda1eaae9eeee766b9249ec5a7ca31fe880882e6b9ce29349ba. Chain 2 (Bitcoin): anchored in block 960387 (2026-07-31T10:06:30Z), 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/USZDG0602421.
Quintet in E-Flat Major for Horn, Violin, Two Violas and Cello, K. 407: III. Allegro
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0x4d13c1bf03a461cbd7d988f85a505e64364e9433eebc39ed5df1504739760e96. 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/USZDG0602422.
Quintet in A Major for Clarinet, 2 Violins, Viola and Violincello, K. 581: II. Larghetto
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0x1ef0aede7cd831de5fdd716cd57456f8dac67b02a354b8be917699f684f5400e. 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/GBKTX1002887.