thumb|Birth house of Leopold Koželuch in Velvary thumb|Prague – Kotzen Theatre thumb|Vienna – Burgtheater Michaelerplatz Leopold Koželuch (, born Jan Antonín Koželuh, alternatively also Leopold Koželu
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 0xfc4aa8f30ba9d15acbec53adeb0ed2403a4dce56bce98f613bff088e0226a25d. 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/aa6a7741-d78f-4e4b-8bb8-f8d693934399.json and https://artists.proofprofile.net/proofs/artist/aa6a7741-d78f-4e4b-8bb8-f8d693934399.ots, the client at https://opentimestamps.org runs `ots verify -f record.json proof.ots`.
Kozeluch: Piano Concertos Nos. 1, 5 & 6 (Hyperion Classical Piano Concerto 4)
Symphony in A Major, P. I:10 "A la française": I. Allegro di molto
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 0x0b1c3519720e825cb0dbaf3e7742159fbe694021cadd123e31053696d208a1d5. Chain 2 (Bitcoin): anchored in block 960410 (2026-07-31T13:50:38Z), 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 at https://artists.proofprofile.net/api/v1/bot/ots/verify/track/HKI191908801 — a six-check JSON result.
Symphony in F Major, Op. 22 No. 2, P. I:4: I. Allegro molto
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0x381779c595c8c0eb1ad9d1285d9cbc1c9ab968d2db081ddceb2f97e05f39be71. 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/HKI191804601 — a six-check JSON result.
Symphony in F Major, Op. 22 No. 2, P. I:4: II. Poco adagio
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0x4f575c8048c52020f7878dbb3ebedd1f566eab1b4413ee2116a3ea1fbf8bdce8. 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/HKI191804602 — a six-check JSON result.
Symphony in F Major, Op. 22 No. 2, P. I:4: III. Menuetto. Allegretto
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0x2b74a829505418c21aacab10e328cc808f7ba25654d237948681e041cce70986. 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 at https://artists.proofprofile.net/api/v1/bot/ots/verify/track/HKI191804603 — a six-check JSON result.
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0xde556be92b202998ba20967bbddd1b9e437b07dd763dd7fe817457b695e027c9. 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/HKI191804605 — a six-check JSON result.
Symphony in D Major, P. I:1: II. Andante
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0xe873e855296e64573d33acb5ec5a36c23dae4166ff6dd872ebc0cc7fd393dd13. 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 at https://artists.proofprofile.net/api/v1/bot/ots/verify/track/HKI191804606 — a six-check JSON result.
Symphony in D Major, P. I:1: III. Rondo. Andantino
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0xf6ef87b2f9a0238c68ae2627015c00e18cabc6d49c777ace13219212f3602e69. 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/HKI191804607 — a six-check JSON result.
Symphony in G Major, Op. 24 No. 3, P. I:8: IV. Presto con fuoco
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0x71a5887fc52abfa927961f084c71650e11577c88aa8382e9d8bdbcc9ab09cc28. Chain 2 (Bitcoin): anchored in block 960164 (2026-07-29T23:23:05Z), 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/HKI191804611 — a six-check JSON result.
Koželuch: Cantata for the Coronation of Leopold II
Kozeluch: Complete Music for Piano 4-Hands
Leopold Kozeluch: 3 Keyboard Sonatas, Op. 1
Kozeluch: Complete Keyboard Sonatas Vol. 4
Kozeluch: Complete Keyboard Sonatas, Vol. 3
Koželuch: Complete Keyboard Sonatas, Vol. 12
Koželuch: Complete Keyboard Sonatas, Vol. 11
Koželuch: Complete Keyboard Sonatas, Vol. 10
Koželuch: Complete Keyboard Sonatas, Vol. 9
Koželuch: Complete Keyboard Sonatas, Vol. 8
Koželuch: Complete Keyboard Sonatas, Vol. 7
Kozeluch: Complete Keyboard Sonatas Vol. 2
Koželuch: Complete Keyboard Sonatas, Vol. 6
Koželuch: Complete Keyboard Sonatas, Vol. 5
Koželuch: Complete Keyboard Sonatas, Vol. 4
Kozeluch: Complete Keyboard Sonatas, Vol. 1
Koželuch: Complete Keyboard Sonatas, Vol. 3
Koželuch: Complete Keyboard Sonatas, Vol. 2
Lost And Found - Oboenkonzerte des 18. Jahrhunderts von Hoffmeister, Lebrun, Fiala und Koželuh
Concerto for Oboe and Orchestra in C Major: I. Allegro con brio
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0x7f2d420772bae8e7ce4554860473a496d2bb103a827d88df21f8eecb7ccc191b. Chain 2 (Bitcoin): anchored in block 959137 (2026-07-22T14:03:35Z), 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/DEN961304101 — a six-check JSON result.
Concerto for Oboe and Orchestra in C Major: II. Adagio
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0x472278b241f8e6bc5d983aeb34a29ec0001266c40c4afd5433764a9d4246e0a7. 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/DEN961304102 — a six-check JSON result.
Concerto for Oboe and Orchestra in C Major: III. Rondo Allegro
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0x66641e3e3853b4fea9ad316130e454ef09fafc60216bddf85cc9b3de7d0620a3. 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/DEN961304103 — a six-check JSON result.
Concerto for Oboe and Orchestra No. 2 in G Minor: I. Allegro
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0x68efaeac624e0a614d62cbd21d73e8ca81ff5cb06dbf3b45d0fa2930445e8ed5. Chain 2 (Bitcoin): anchored in block 960247 (2026-07-30T10:42:33Z), 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 at https://artists.proofprofile.net/api/v1/bot/ots/verify/track/DEN961304111 — a six-check JSON result.
Concerto for Oboe and Orchestra No. 2 in G Minor: II. Adagio
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0x5c88b45a330835f49ea5030c3d39a357c992ecd08d44c5e0fdc18af53f024252. Chain 2 (Bitcoin): anchored in block 960291 (2026-07-30T18:23:33Z), 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 at https://artists.proofprofile.net/api/v1/bot/ots/verify/track/DEN961304112 — a six-check JSON result.
Concerto for Oboe and Orchestra No. 2 in G Minor: III. Rondo Allegro
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0xbd0cbb03948c17934826bdca22814caa7419bf7b0b56f5d61ea3fdd30117ef62. Chain 2 (Bitcoin): anchored in block 960317 (2026-07-30T21:35:24Z), 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/DEN961304113 — a six-check JSON result.
Concerto for English Horn and Orchestra in C Major: I. Allegro moderato
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0x6b321147a871534ac22e9b3c95619a1510dee06fcc57da723fdfd7e1512abba1. 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/DEN961304121 — a six-check JSON result.
Concerto for English Horn and Orchestra in C Major: II. Adagio cantabile
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0x8ab34d366ff0cac7dce92640e83f4cff831bb17708fea0bb8c689e381759943c. 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/DEN961304122 — a six-check JSON result.
Concerto for English Horn and Orchestra in C Major: III. Allegro assai
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0x03ac1c3ed5a9bd3c24399a6f2fb91122f18b097fbafc22c4b6b35f8df0cd5d9a. 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/DEN961304123 — a six-check JSON result.
Concerto for Oboe and Orchestra in F Major: I. Vivace
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0x3814f392c27cfecfd1e3a07e149799d2c9cc4ce8eddc5cf52a9a1d35a889316f. 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 at https://artists.proofprofile.net/api/v1/bot/ots/verify/track/DEN961304131 — a six-check JSON result.
Concerto for Oboe and Orchestra in F Major: II. Adagio
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0x31d03d2f4e6d6c6b84313499653dd97062bbb81221658046c26d417a9095da58. 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/DEN961304132 — a six-check JSON result.
Concerto for Oboe and Orchestra in F Major: III. Rondo Allegretto
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0x85951bdb16a61ce9a66502dfd69daa81c1258cc1a879cceb3e4a7a4c3bef48d8. Chain 2 (Bitcoin): anchored in block 960473 (2026-07-31T22:27:44Z), 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/DEN961304133 — a six-check JSON result.
Leopold Koželuh: Trios for Flute, Cello and Piano II.
Leopold Koželuh: Piano Sonatas, Op. 26 & 38
Leopold Koželuh: Piano Sonatas, Op. 2 & 30
Leopold Koželuh: Piano Sonatas, Op. 15, 17 & 20
Leopold Koželuh: Keyboard Sonatas Op. 1, 5 & 13
Koželuch: Complete Keyboard Sonatas, Vol. 1
Koželuh: Sonatas for Fortepiano, Flute and Cello
Kozeluch: Piano Concertos Nos. 1, 4 and 5
Piano Concerto No. 1 in F Major: I. Allegro
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0x5ae568bbf79042fe91e579e9c31241e7601e463ec799490dc8e4f8a133ee5e38. 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/DEU920658801 — a six-check JSON result.
Piano Concerto No. 1 in F Major: II. Adagio
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0xed6d34c9be7a36432cb95f9e9b11f5b63d3f4083656389e32dd4c1bdef762684. 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/DEU920658802 — a six-check JSON result.
Piano Concerto No. 1 in F Major: III. Rondo: Allegro
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0xf64acaebe145993ad6487af691283b5970541788b13c99ba04f945ddb5c5c01f. Chain 2 (Bitcoin): anchored in block 960429 (2026-07-31T16:07:24Z), 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/DEU920658803 — a six-check JSON result.
Leopold Kozeluch: Keyboard Sonatas, Op. 2 Nos. 1 & 2
Concerto for Bassoon and Orchestra in C Major, LMik. JAK XIV:1: I. Allegro
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0xe2b12c49981463b6423aadbab0206aef203346c27b76d5bd7cc9872cf3815871. 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/DEE862001822 — a six-check JSON result.
Concerto for Bassoon and Orchestra in C Major, LMik. JAK XIV:1: III. Allegro assai
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0x9bcaa1d6cb23c74f7a229b4f2558f11214d952ea169e79835f9744ae7ee95b72. Chain 2 (Bitcoin): anchored in block 960481 (2026-07-31T23:51:35Z), 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/DEE862001824 — a six-check JSON result.