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
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0x252faf52f159a0a422b924e80c0f8dd2a68755cb0aa0ee03fb0658953f23b45a. Chain 2 (Bitcoin): anchored in block 954516 (2026-06-20T07:04:44Z). Bridge: the canonical record inside this Bitcoin proof contains the same CopyrightID. Verify: download https://artists.proofprofile.net/proofs/artist/9fe27532-2c1c-4e7b-9e46-09277422565a.json and https://artists.proofprofile.net/proofs/artist/9fe27532-2c1c-4e7b-9e46-09277422565a.ots, run `ots verify -f record.json proof.ots` (https://opentimestamps.org).
Hindemith: Quartet for Clarinet, Violin, Cello and Piano & Shostakovich: Piano Quintet in G Minor, Op. 57
Spohr: Nonet in F Major, Op. 31 - Coker: Concertino for Bassoon and String Trio, Op. 31 - Barber: Summer Music, Op. 31 - Coker: Concertino (2022 Remastered Version)
Profanes Et Sacrées: 20th Century French Chamber Music
Plain Song, Fantastic Dances: Chamber Music by American Composers
Mozart Chamber Music for Winds and Strings
Clarinet Quintet in A Major, K. 581: II. Larghetto
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
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0x6bef9442d89b6d5584cf70b0ef7367c0226f0e51ebddd7e4fd8555bf41c23d6f. 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/USZXG0600602.
Clarinet Quintet in A Major, K. 581: III. Menuetto
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0x60385dbaccb97bf7b30323e5429306ff591f589713657ba0e677a650eec1e84b. Chain 2 (Bitcoin): anchored in block 957061 (2026-07-07T16:07:00Z), 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/USZXG0600603.
Clarinet Quintet in A Major, K. 581: IV. Allegretto con variazioni
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0x6d55368c93e433964920fa269327476ecd15c527f23833dcd1329b2929b1d738. Chain 2 (Bitcoin): anchored in block 956312 (2026-07-02T05:09:12Z), 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/USZXG0600604.
Oboe Quartet in F Major, K. 370/ 368b: I. Allegro
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0x9ef2a139a91690b23067187e6aa660b1696b8629491f6c8fe42bd56c789ce117. 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/USZXG0600608.
Oboe Quartet in F Major, K. 370/ 368b: II. Adagio
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0x1278f200ef97374c4ff0e7e60a22dadca74a35315e4e26d09a3826e519666ff0. 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/USZXG0600609.
Flute Quartet in A Major, K. 298: I. Theme (Andante) and Variations
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0x0bd6c4a090e5e85327cad02e955f15a53f4f3c648639ce9e7fcd07bfc11a2ae4. 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/USZXG0600611.
Flute Quartet in A Major, K. 298: II. Menuetto
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0x94f928a2c7848d2fa6d4b7bbecf1b522c218adaae01d84e69997298fe2e72c32. Chain 2 (Bitcoin): anchored in block 957124 (2026-07-08T03:53:27Z), 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/USZXG0600612.
Flute Quartet in A Major, K. 298: III. Rondeau - Allegretto grazioso
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0x4fc2cea88c3c30bd677402e9c76095b1597e7c04c5b1e73311c2e3f8518e680a. 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/USZXG0600613.
Clarinet Quintet in A Major, K. 581: I. Allegro
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0xa1bc90d2938313ea73b869fab14df0765e64307b7fa88e9022fb9699070b7430. Chain 2 (Bitcoin): anchored in block 960185 (2026-07-30T01:32:48Z), 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/USZXG0600601.
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
Horn Quintet in E Flat Major, K. 407: I. Allegro
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0x1b1ee424de41af05d08f7c5396ab331dc966fc0988da43740bc2d35a64c60178. Chain 2 (Bitcoin): anchored in block 960334 (2026-07-31T02:19:15Z), 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/USZXG0600605.
Horn Quintet in E Flat Major, K. 407: II. Andante
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0x2fd29a6f8a6f73880ed83a1bbaa2a062085d91110d404bb9820c30202f575d5b. Chain 2 (Bitcoin): anchored in block 960344 (2026-07-31T04:14:58Z), 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/USZXG0600606.
Horn Quintet in E Flat Major, K. 407: III. Rondo - Allegro
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0x3bff07bc75c72dfe75e8af7e0f28f276925c8600b773a894f5f79601066f03d8. Chain 2 (Bitcoin): anchored in block 960354 (2026-07-31T05:48:18Z), 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/USZXG0600607.
Oboe Quartet in F Major, K. 370/ 368b: III. Rondeau - Allegro
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0x6d7b0d9778022499abd1d1f0a6b584719417d710b6ba2e69c01014385c6b1bb5. Chain 2 (Bitcoin): anchored in block 960334 (2026-07-31T02:19:15Z), 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/USZXG0600610.
Schubert: Piano Trio, Op. 99 - Milhaud: Pastorale - Hindemith: Kleine Kammermusik, Op. 24, No. 2 (2022 Remastered Version)
The Boston Symphony Chamber Players Play Schubert, Brahms, Poulenc, Webern and Martinu (2022 Remastered Version)
The Boston Symphony Chamber Players Play Mozart, Brahms, Beethoven, Fine, Copland and Carter (2022 Remastered Version)
The Boston Symphony Chamber Players Play Mozart, Brahms, Schubert, Poulenc, Cograss, Villa-Lobos and Haieff (2022 Remastered Version)
Chamber Music Discussions with Peter Ustinov, Erich Leinsdorf and Joseph Silverstein (2022 Remastered Version)