Gustav Maria Leonhardt (30 May 1928 – 16 January 2012) was a Dutch keyboardist, conductor, musicologist, teacher and editor. He was a leading figure in the historically informed performance movement t
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 0x7c00c2f4358f1507fd472ebd73341ea89502ef48e81811314583d05531b65f1c. 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/f456d4da-f3f0-4200-b695-9cef2c69fc51.json and https://artists.proofprofile.net/proofs/artist/f456d4da-f3f0-4200-b695-9cef2c69fc51.ots, run `ots verify -f record.json proof.ots` (https://opentimestamps.org).
Recorder Concerto in F Major: I. Allegro
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 0x0bedae9e3ef9f3845ed13e529eb995df4cecd571c80492cd175036ee6fcb0809. Chain 2 (Bitcoin): anchored in block 957145 (2026-07-08T08:56:20Z), 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/ITX921002114.
Recorder Concerto in C Major, RV 443: I. Allegro
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0x62af62a19949a496ddaf242b51d6ddb16465b841b4f9c7a02d9f78c6e3d53a72. 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/ITX921002117.
Recorder Concerto in C Major, RV 443: II. Largo
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0x9e734b7d1522d60c83db5da4ba919a513d69f4b43ff3c03ed4ac50a37dd03126. 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/ITX921002118.
Recorder Sonata in C Major, TWV 41:C5: I. Adagio - Allegro
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0xad7db1ef91468ddb738839de566f7529154a50def4a166b1c09778a49354b522. Chain 2 (Bitcoin): anchored in block 960403 (2026-07-31T13:04:34Z), 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/ITX921002127.
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
J.S. Bach: Secular Cantatas Nos. 208 & 215
J.S. Bach: Secular Cantatas BWV 173a & 201
Bach, J.S.: Easter Oratorio/Ascension Oratorio (Audior)
Kommt, eilet und laufet (Easter Oratorio), BWV 249: 1a. Adagio
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0x9549d6883b513bc35fc2ccded011a6803a58463d66c5253e48cb1556fb4010e5. Chain 2 (Bitcoin): anchored in block 957304 (2026-07-09T12:19:34Z), 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/NLA509304702.
Purcell Edition Volume 3 : Odes, Anthems & Ceremonial Music
Bach, JS: Christ unser Herr zum Jordan kam, BWV 7: No. 2, Aria. "Merkt und hört, ihr Menschenkinder"
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0x809206245b781af2a3b5bcf0f836d31ea90d3e0af3f240327a657417cd474edd. 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/DEA807101402.
Bach, JS: Christ unser Herr zum Jordan kam, BWV 7: No. 4, Aria. "Des Vaters Stimme ließ sich hören"
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0x08a12e46fea30f79969a43a927f2fd4ddb89639e9ab5f761b2f4d94d21258667. 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/DEA807101404.
Bach, JS: Christ unser Herr zum Jordan kam, BWV 7: No. 5, Rezitative. "Als Jesus dort nach seinen Leiden"
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0xcaeba2ac9b20ed17fb1f287eea1650da38fddcab967df939673ddfcf5e8bfff7. 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/DEA807101405.
Bach, JS: Liebster Gott, wann werd ich sterben, BWV 8: No. 1, Chor. "Liebster Gott, wenn werd ich sterben?"
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0x5a0de557d727d9918ff6a6eb216a7d36a7a477f984c9e4420efb6e3633945ae2. 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/DEA807101201.
Bach, JS: Liebster Gott, wann werd ich sterben, BWV 8: No. 3, Rezitativ. "Zwar fühlt mein schwaches Herz"
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0x9bcdb0dafce36ae2d5f4c72aec51627ca30f4650974ccb6f745bac19b72ba1a8. 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/DEA807101203.
Bach, JS: Liebster Gott, wann werd ich sterben, BWV 8: No. 4, Aria. "Doch weichet, ihr tollen, vergeblichen Sorgen!"
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0xf70a83179bb65d2d11a915488c7bc745e15434da0b6a666dac0be88d7e15614f. 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/DEA807101204.
Bach, JS: Christ unser Herr zum Jordan kam, BWV 7: No. 1, Chor. "Christ unser Herr zum Jardan kam"
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0x56584cb9d37acf35b79c425851d852cfa60a7e58690101789e0c266b6d47f763. 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/DEA807101401.
Bach, JS: Christ unser Herr zum Jordan kam, BWV 7: No. 6, Chorale. "Menschen, glaubt doch dieser Gnade"
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0xcbfd5b7af693803fec1d9a573f906c1e62476a852d74461b5ab2e77a80e12395. Chain 2 (Bitcoin): anchored in block 960441 (2026-07-31T17:29:52Z), 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/DEA807101406.
Bach, JS: Liebster Gott, wann werd ich sterben, BWV 8: No. 2, Aria. "Was willst du dich, mein Geist, entsetzen"
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0x3cacb9e775995bf9834c74dadf2dfdedf36d49100bb7813946683bc92ccb9f25. Chain 2 (Bitcoin): anchored in block 960418 (2026-07-31T15:20:15Z), 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/DEA807101202.
Bach, JS: Es ist das Heil uns kommen her, BWV 9: No. 3, Aria. "Wir waren schon zu tief gesunken"
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0x88e4deb33d2128bb8321f6920c9306d9d996bc987409fdfd0c18e0b0afd7a472. Chain 2 (Bitcoin): anchored in block 960381 (2026-07-31T09:50:11Z), 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/DEA807102903.
Bach, JS: Es ist das Heil uns kommen her, BWV 9: No. 5, Duett. "Herr, du siehst statt guter Werke"
Soloist of the Regensburg Cathedral Choir
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0x4987c4377656b1c63ea5f18853b561fa43dc4a2f0da5f1858c4b6ac809c4793b. Chain 2 (Bitcoin): anchored in block 960427 (2026-07-31T15:59:18Z), 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/DEA807102905.
Bach, JS: Meine Seel erhebt den Herren, BWV 10: No. 1, Choral Fantasie. "Meine Seel erhebt den Herren"
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0xdfe0c0183080f7259719d0cdc2a0ef2fdf3f0c40ed126e8dce6816e3e05658ee. 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/DEA807103001.
Bach, JS: Lobet Gott in seinen Reichen, BWV 11 "Himmelfahrtsoratorium": No. 1, Chor. "Lobet Gott in seinen Reichen"
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0xbf77e1f3f007f88f7b73be3c56fa002ab4c93efbca794aa792f1b3bccdbd99b2. Chain 2 (Bitcoin): anchored in block 957145 (2026-07-08T08:56:20Z), 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/DEA807101301.
Bach, JS: Lobet Gott in seinen Reichen, BWV 11 "Himmelfahrtsoratorium": No. 11, Choral. "Wenn soll es doch geschehen“
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0xff2dcaa116a4ff82dab7de67d92f54951f8a229faf5a7f1ad22e1ac93270fd5f. 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/DEA807101311.
Bach, JS: Meine Seel erhebt den Herren, BWV 10: No. 2, Aria. "Herr, der du stark und mächtig bist"
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0x34123b5778d3d65add695a947eb2aeb99c996bb3f71ec229b9e19c5da1171dd2. Chain 2 (Bitcoin): anchored in block 960448 (2026-07-31T18:48:12Z), 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/DEA807103002.
Bach, JS: Weinen, Klagen, Sorgen, Zagen, BWV 12: No. 1, Sinfonia
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0x04208d6c43c611eedd0340fe38b5813cf7efab3d735f780357223e6c437d82bb. 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/DEA807200701.
Bach: Notebook for Wilhelm Friedemann Bach: No. 8, Prelude in F Major, BWV 927
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0x4da73cb4d95aef04dc7f8f939367aa2b7a1c9f02685d596a3e6243206adc566b. 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/DEA806417200.
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0xf051ea3adbf2a5a4175c9ba42c83556373311af86ae8bfafba2804e684e7afa6. 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/USX760801019.
Come ye sons of art, 1694, ode for Queen Mary (excerpts)
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0x7dc30ad46c2da68fdfb6a26c3f72d328c94bd4fbd4651013ceb6abe99cda580f. 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/GBAYC9105759.
Schweigt stille, plaudert nicht, BWV 211 "Coffee Cantata": 8. Aria: "Heute noch, lieber Vater, tut es doch"
Barbara Bonney - The Radiant Voice of Barbara Bonney
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0x9e68c0e635f995cdd5845072257b3b9602c39ba420d5939413cd98151e9f7dfd. 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/NLA509404008.
Le Bourgeois Gentilhomme - Comédie-Ballet, LWV 43: Ouverture
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0x4b7a1ca8b19f6431c00dcb0f1a335abf9194b9ade0055f5fea4efbfa5264a518. 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/DEE478800135.
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0xf518c0d931c3ed1c34234b698c2bc0ee8b4d6c56b3d5cfe173de4f4edacc6031. Chain 2 (Bitcoin): anchored in block 960254 (2026-07-30T12:06:10Z), 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/FR50X0304206.