Otakar Kraus OBE (10 December 1909 — 28 July 1980) was a Czech (later British), operatic baritone and teacher. He was born in Prague and studied there with Konrad Wallerstein and in Milan with Fernan
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 0x2dadd6ac478098ad269d9daf5699bda290926b62c6671f15af8342788630a254. Chain 2 (Bitcoin): anchored in block 953949 (2026-06-16T13:28:01Z). Bridge: the canonical record inside this Bitcoin proof contains the same CopyrightID. Verify: download https://artists.proofprofile.net/proofs/artist/13ec348e-372d-4064-a508-fdb16483386b.json and https://artists.proofprofile.net/proofs/artist/13ec348e-372d-4064-a508-fdb16483386b.ots, run `ots verify -f record.json proof.ots` (https://opentimestamps.org).
Legenden der Operette: Elisabeth Schwarzkopf
Lehár: Das Land des Lächelns & Other Operetta Excerpts
Bach: St Matthew Passion, BWV 244 (Remastered)
Bach, JS: Matthäus-Passion, BWV 244, Pt. 1: No. 3, Choral. "Herzliebster Jesu, was hast du verbrochen"
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 0x3fe96128f3994f6adb637634f60a0c51a29cfc012fb5eb19a5c0a50fa40f0e4a. 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/GBAYC2300989.
Bach, JS: Matthäus-Passion, BWV 244, Pt. 1: No. 4d, Chor. "Wozu dienet dieser Unrat"
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0xe0df0f2852104253a36b70d7842d7c9f794f1ab7403cadfe3415ebe82fb18293. 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/GBAYC2300993.
Bach, JS: Matthäus-Passion, BWV 244, Pt. 1: No. 14, Rezitativ. "Und da sie den Lobgesang gesprochen hatten"
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0xe7461f64763a8b38094286dc3d7d4b74df8cb4e2ee5eae83a6283ff42a949d0a. 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/GBAYC2301006.
Bach, JS: Matthäus-Passion, BWV 244, Pt. 2: No. 32, Choral. "Mir hat die Welt trüglich gericht"
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0x9a252f20df379f7e9b0b90b5022297554f164da01cc2d4fa08f2c82053394f1e. 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/GBAYC2301024.
Bach, JS: Matthäus-Passion, BWV 244, Pt. 2: No. 37, Choral. "Wer hat dich so geschlagen"
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0x74c050bb6899594aa1e22eed92c40efef118f7fec0d9694d0d06096b1da45470. 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/GBAYC2301030.
Bach, JS: Matthäus-Passion, BWV 244, Pt. 1: No. 1, Chor. "Kommt, ihr Töchter helft mir klagen"
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0xbd6117779ed602609203542bfe066ef90d75be27313d4988d7a9d7759c921145. Chain 2 (Bitcoin): anchored in block 956894 (2026-07-06T07:53:57Z), 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/GBAYC6100172.
Bach, JS: Matthäus-Passion, BWV 244, Pt. 1: No. 27, Aria und Chor. "So ist mein Jesus nun gefangen"
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0xfe150cb28d5b08ed3aab80991220d746d5ff0210873e8e6a5fb605566824f6ce. 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/GBAYC6100204.
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0xe7609faf7eb86aa06f3fea5b58f63953c58815aa27f795e41f613fda88af6a4a. 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/GBAYC6100174.
Bach, JS: Matthäus-Passion, BWV 244, Pt. 1: No. 4a, Rezitativ. "Da versammleten sich die Hohenpriester"
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0xbe0a2d1d9a1f440c243e22f5994a16aac48fc5f1947da7d8011dc202fcaa75c9. 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/GBAYC6100175.
Bach, JS: Matthäus-Passion, BWV 244, Pt. 2: No. 30, Aria mit Chor. "Ach, nun ist mein Jesus hin!"
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0x5f119cf879b316e743c8ef2f54b1661f65f190b12d724a4fd74650067fca112b. 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/GBAYC6100208.
Bach, JS: Matthäus-Passion, BWV 244, Pt. 2: No. 31, Rezitativ. "Die aber Jesum gegriffen hatten"
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0x5ee9604f47d7f2c63ec61de91f8b2525f1542ce5ac5e999623de75347caa080f. 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/GBAYC6100209.
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0xd08ddc47df0430a2521190562eb0095ece91febc78958c4bd238f2f6da78076c. 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/GBAYC6100178.
Bach, JS: Matthäus-Passion, BWV 244, Pt. 1: No. 4e, Rezitativ. "Da das Jesus merkete"
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0x35080f2c52b3bee252f1727a59d9e48b3f7fff17c39f4beebf70ae28949d764b. 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/GBAYC6100179.
Bach, JS: Matthäus-Passion, BWV 244, Pt. 1: No. 5, Rezitativ. "Du lieber Heiland du"
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0xa95bac8960f8fe3be1dd8b9851d81ece96d0ab0a595e4c7ad7b062e37551446f. 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/GBAYC6100180.
Bach, JS: Matthäus-Passion, BWV 244, Pt. 2: No. 35, Aria. "Geduld!"
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0xd38277163e7f49fd09ab5e4a6d415b18ea3dce3d2451f6f4fcf077d197479cea. 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/GBAYC6100213.
Bach, JS: Matthäus-Passion, BWV 244, Pt. 2: No. 36c, Rezitativ. "Da speieten sie aus"
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0xa784247e360d8d6d94e5e9f53a7bbc603a8802e24b5d5648abda14c0897c7dc0. 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/GBAYC6100215.
Bach, JS: Matthäus-Passion, BWV 244, Pt. 1: No. 9c, Rezitative und Chor. "Er sprach. Gehet hin in die Stadt"
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0x575f84dbc3825daa36a1b43bffc8ca2870fd21370f5ea99637789b42c16b91d2. 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/GBAYC6100186.
Bach, JS: Matthäus-Passion, BWV 244, Pt. 2: No. 38c, Rezitativ. "Da hub er an, sich zu verfluchen"
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0x8739b6833ce32d0bc8a8da91fe4dd83fb77b18a47cbee4684cebfbef539b3b49. 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/GBAYC6100218.
Bach, JS: Matthäus-Passion, BWV 244, Pt. 1: No. 10, Choral. "Ich bin's, ich sollte büßen"
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0x1aa03e1a90163f1abb5868333111cfd25465da642cf8f0b720245cc27f9fb3c6. 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/GBAYC6100187.
Bach, JS: Matthäus-Passion, BWV 244, Pt. 1: No. 11, Rezitativ. "Er antwortete und sprach"
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0x44ad150dfc2699e8f77e78e065f1a2c9ae2108e8a8a47e9fa53543b06cc743d5. 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/GBAYC6100188.
Bach, JS: Matthäus-Passion, BWV 244, Pt. 1: No. 12, Rezitativ. "Wiewohl mein Herz in Tränen schwimmt"
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0x4f780446ed9281a7c54b966417f4d10ae019db693b37f8eef3cd6cdac397de09. 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/GBAYC6100189.
Bach, JS: Matthäus-Passion, BWV 244, Pt. 2: No. 41c, Rezitativ. "Und er warf die Silberlinge in den Tempel"
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0x684acaac55d5e5611ae737815686624ad12ae16cce501ca2e5e8cecd0f3122af. 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/GBAYC6100222.
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0x616ec382864328a835ce4332256339c1f7df56fbf5bdcc11276771e2e6bd7744. 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/GBAYC6100191.
Bach, JS: Matthäus-Passion, BWV 244, Pt. 1: No. 15, Choral. "Erkenne mich, mein Hüter"
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0x1b55242bb989f42c4a23b1f6e3335b410f0cb8c48ab49ed6208a1acc39910db0. 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/GBAYC6100192.
Bach, JS: Matthäus-Passion, BWV 244, Pt. 1: No. 17, Choral. "Ich will hier bei dir stehen"
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0xb5f0c575445d01382d3fc8b69713f821a3e98e527be425ab2896dab9270ac144. Chain 2 (Bitcoin): anchored in block 957122 (2026-07-08T03:39:04Z), 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/GBAYC6100194.
Bach, JS: Matthäus-Passion, BWV 244, Pt. 1: No. 25, Choral. "Was mein Gott will, das g'scheh allzeit"
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0x61cad613df6458820a36a9d6fcb0dc90d235c977c958b088591547c634afc676. 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/GBAYC6100202.
Bach, JS: Matthäus-Passion, BWV 244, Pt. 2: No. 36a, Rezitativ und Chor. "Und der Hohepriester antworte"
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0xd9011ec01465e4ba40fa448184be3b08e169cd7ac1f17d0ed639f4ba1ddc84e1. 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/GBAYC6100214.
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
Bach: St Matthew Passion, Violin Concertos, No. 1 & 2, Concerto for 2 Violins
Strauss, R: Ariadne auf Naxos, Op. 60, Opera: "Hübsch gepredigt! Aber tauben Ohren!" (Harlekin, Zerbinetta, Brighella, Scaramuccio, Truffaldin)
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0x478d6ba2328d491b7444c868556f3baa77c31c7b08826be1bc21a403da90b83f. 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/GBAYC9900491.
Strauss, R: Ariadne auf Naxos, Op. 60, Prologue: "Für einen Bacchus!" (Tenor, Composer, Wigmaker)
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0xf935f769ef01130bb9b83b18d910f922f1a9a2ee6a1be951cdf74c9efa79b81a. 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/GBAYC9900472.
Lehár: Die Lustige Witwe & Das Land Des Lächelns
Berg, Stravinsky & Vaughan Williams: Orchestral Works (Live)
Meine Lippen, sie küssen so heiß: das Schönste der Operette
Lehar: Merry Widow (The) (Schwartzkopf, Kunz, Gedda) (1953)
The Hoffnung Interplanetary Music Festival, 1958
Strauss, R: Ariadne Auf Naxos (Schwarzkopf, Streich, Karajan) (1954)
Lehar: Das Land des Lächelns/Die Lustige Witwe
La Carrière Du Libertin (Acte 1 & Acte 2) : Anthologie Igor Stravinsky Vol. 8
La Carrière Du Libertin (Acte 2 & Acte 3) : Anthologie Igor Stravinsky Vol. 9