Hans Kann (born 14 February 1927 in Vienna; died 24 June 2005) was an Austrian pianist and composer. He taught music in his native Austria and in Japanese schools such as the Tokyo National University
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 0xb56b2864c18bd1e5acc8f3903baa5a0ef18498981879a3a943a2da7ce25706a0. Chain 2 (Bitcoin): anchored in block 953877 (2026-06-16T02:39:16Z). Bridge: the canonical record inside this Bitcoin proof contains the same CopyrightID. Verify: download https://artists.proofprofile.net/proofs/artist/082cf109-a2a4-44f8-98da-a333d404c1cf.json and https://artists.proofprofile.net/proofs/artist/082cf109-a2a4-44f8-98da-a333d404c1cf.ots, the client at https://opentimestamps.org runs `ots verify -f record.json proof.ots`.
Madrigals & Keyboard Music of the English Renaissance
Kalkbrenner: Piano Concerto No. 1 - Hummel: Piano Concerto No. 4
Piano Concerto No. 1 in D Minor, Op. 61: I. Allegro maestoso
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 0xc4c00dfbad6f8ae876c0f78946a14a0b5e0e3162db03e55eb45866f784a0decb. 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/HKI192331211 — a six-check JSON result.
Piano Concerto No. 1 in D Minor, Op. 61: II. Adagio di molto
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0xf15c6602fbc8dd8e7239033926cf2996b4ed88b0967664889a42be8e254df6a7. 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 at https://artists.proofprofile.net/api/v1/bot/ots/verify/track/HKI192331212 — a six-check JSON result.
Piano Concerto No. 1 in D Minor, Op. 61: III. Rondo. Vivace
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0x0c5045b6d80293e4fb2c2cef871b3e4968531b1a890fb64e5e84c2da6df0c42a. Chain 2 (Bitcoin): anchored in block 960160 (2026-07-29T22:48:59Z), 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/HKI192331213 — a six-check JSON result.
Piano Concerto No. 4 in E Major, Op. 110: II. Andante con moto
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0xfe7d917d4f55fd09ec685aaab77a771bc46e80d4f235c710b8e73429d87b239f. 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/HKI192331215 — a six-check JSON result.
Hummel: Concerto for Mandolin and Orchestra
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0x88b48bad18c2235b69cfddd0e9d9df2af5d75748db76ee6b44b39ac48777c247. Chain 2 (Bitcoin): anchored in block 956474 (2026-07-03T08:56:35Z), 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/ATP139641916 — a six-check JSON result.
Johann Sebastian Bach - Die 'Goldberg-Variationen' - Hans Kann (
Classical Selection - Hummel & Kalkbrenner: Piano Concertos
Beethoven & Liszt: Piano Concerto NO. 2, OP. 73 - Hungarian Rhapsody NO. 2
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0xfee38cedc6a7083a6fd46f3008b57813419e41c14cca1b0407c0003c8394d52b. 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 at https://artists.proofprofile.net/api/v1/bot/ots/verify/track/USZGD9200133 — a six-check JSON result.