thumb|Manfred Gurlitt in 1942 Manfred Gurlitt (6 September 1890 – 29 April 1972) was a German opera composer and conductor. He studied composition with Engelbert Humperdinck and conducting with Karl
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 0xd9a81062c6f8183a55d24580b67cd90a3a96b806494e6e85d4eed5c1120a2b25. Chain 2 (Bitcoin): anchored in block 954659 (2026-06-21T06:14:42Z). Bridge: the canonical record inside this Bitcoin proof contains the same CopyrightID. Verify: download https://artists.proofprofile.net/proofs/artist/dc2906a0-a6d3-42f8-9a55-f5cd22a90726.json and https://artists.proofprofile.net/proofs/artist/dc2906a0-a6d3-42f8-9a55-f5cd22a90726.ots, the client at https://opentimestamps.org runs `ots verify -f record.json proof.ots`.
Strauss, R.: Rosenkavalier (Der) (Lehmann, Schumann) (1933)
Julius Patzak - The Early Operatic Recordings
Composers In Exile - Zemlinsky, A. Von / Schreker, F. / Schulhoff, E. / Ullmann, V. / Hindemith, P. / Schoenberg, A. / Milhaud, D.
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 0x144cc490cc6615a5d71eb84fd77134e45a833031c9a8ff93a378b569fc4c1b67. 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 at https://artists.proofprofile.net/api/v1/bot/ots/verify/track/US2TL0943804 — a six-check JSON result.
Duo for Violin and Cello: II. Zingaresca: Allegro giocoso
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0x1b9644b8ffaadab9d564a8e71f56ea7da8b5fe04719a1b94f19d6fda51a41945. Chain 2 (Bitcoin): anchored in block 960360 (2026-07-31T06:42:11Z), 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 at https://artists.proofprofile.net/api/v1/bot/ots/verify/track/US2TL0943806 — a six-check JSON result.
String Quartet No. 1, Op. 5: I. Rhythmique
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0x2d40f1d0fe741e14cff3921e020cefb72ede2f0ad01bea6c552cccb587238398. 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 at https://artists.proofprofile.net/api/v1/bot/ots/verify/track/US2TL0943819 — a six-check JSON result.
String Quartet No. 1, Op. 5: II. Intime, contenu
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0xc48b9e217f7398903b037398dfb7b0c5161df313b747d93ccd4a2384fc96b2e6. Chain 2 (Bitcoin): anchored in block 960397 (2026-07-31T12:24:41Z), 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 at https://artists.proofprofile.net/api/v1/bot/ots/verify/track/US2TL0943820 — a six-check JSON result.
String Quartet No. 1, Op. 5: III. Grave, soutenu
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0x10a72fbe81980cfdae1d86a015af8f09f50cb9e04ab75f406ed11df7d3737387. 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 at https://artists.proofprofile.net/api/v1/bot/ots/verify/track/US2TL0943821 — a six-check JSON result.
Kleine Sinfonie, Op. 29: I. Thema mit Variationen
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0x9241d673635c0d57c6fa275d7d8cdecb6d2cc5fb0660b611e63b11e9fc5afa4d. Chain 2 (Bitcoin): anchored in block 960463 (2026-07-31T20:42:35Z), 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 at https://artists.proofprofile.net/api/v1/bot/ots/verify/track/US2TL0943823 — a six-check JSON result.
Puccini: Turandot (Sung in German) [Recorded Live 1956]
The Richard Tauber Collection, Vol. 10: Opera Scenes (1927-1946)
Heroes and Heroines of Bayreuth: Franz Volker (Historical Recordings 1928-1941)
Gurlitt, M.: Goya-Sinfonie (Goya-Symphony) / 4 Dramatic Songs
Gurlitt: Goya-Symphony & Vier dramatische Gesänge für Sopran und Orchester (World Premiere Recording)
Verdi: La Traviata: Ach, ihres Auges Zauberblick (Alfredo's Aria) [Sung in German]
Smetana: The Bartered Bride: Jenik's Aria
Beethoven: Fidelio, Op. 72: Abscheulicher! Wo eilst du hin?
Verdi: La Traviata: Hat dein heimatliches Land (Sung in German)
Verdi: Il Trovatore: Sieh' meiner hellen Tränen Flut (Sung in German)
Mozart: Don Giovanni, K. 527: Treibt der Champagner (Sung in German)
Mozart: Violin Concerto No.5 in A Major, K.219
The Richard Tauber Collection, Vol. 15: Operetta Scenes (1924-1933)
Gurlitt: Goya-Symphony & Vier dramatische Gesänge für Sopran und Orchester
The Great Violinists, Vol. 6 (1928-1932)
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0x49754b202b7aa61de379353fa68b3476d4fd7d1a392eaffc88f167d782cd4b80. 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 at https://artists.proofprofile.net/api/v1/bot/ots/verify/track/DEF050702020 — a six-check JSON result.
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0xd44a7d34fc3a17fd5306fd2177acd7dde128377d70557797014b7b71ff4a5111. Chain 2 (Bitcoin): anchored in block 960284 (2026-07-30T17:23:26Z), 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 at https://artists.proofprofile.net/api/v1/bot/ots/verify/track/DEF050702030 — a six-check JSON result.
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0x28fef8d3d52a17e34a182f00e963b0f037a003d3cc6a31ca6ecccb7afd25899f. Chain 2 (Bitcoin): anchored in block 960397 (2026-07-31T12:24:41Z), 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 at https://artists.proofprofile.net/api/v1/bot/ots/verify/track/DEF050400003 — a six-check JSON result.
Voi lo sapete, o mamma (Cavalleria rusticana)
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0xa97d29c207e6a2967912d0e5dbc0168d6223c5a39673562c7dabf7925a1c2a0b. 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 at https://artists.proofprofile.net/api/v1/bot/ots/verify/track/GBAYC0802087 — a six-check JSON result.
Lohengrin, WWV 75 / Act 2: "Euch Lüften, die mein Klagen"
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0xa6cdc102368f6720e28755e68e178ab61f4154eb81b9d9742ffae5d9a48ac18c. 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 at https://artists.proofprofile.net/api/v1/bot/ots/verify/track/DEF056705070 — a six-check JSON result.
Tristan und Isolde, WWV 90 / Act III: Mild und leise wie er lächelt - Live at Bayreuther Festspiele / 1966
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0x5a7e736321b6dc18c1d54bd1eb7e6a4c686768b960d9b504bd293358a695d364. 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 at https://artists.proofprofile.net/api/v1/bot/ots/verify/track/DEF056630206 — a six-check JSON result.
Lieder von Franz Schubert in historischen Aufnahmen
DG 120 – Chamber Music: Early Recordings
Lebendige Vergangenheit - Heinrich Rehkemper
Lebendige Vergangenheit - Karin Branzell (Vol. 2)