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 0xbdd7cb645e128c02f5e9105ca3eed2c37f3de54c84fab0096a0745907b33ea8a. 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/62e9ec4b-b457-4011-b34f-855f20ea5941.json and https://artists.proofprofile.net/proofs/artist/62e9ec4b-b457-4011-b34f-855f20ea5941.ots, the client at https://opentimestamps.org runs `ots verify -f record.json proof.ots`.
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 0xac0b7e8f142b0b6a0347fccc4751b077f2c04bdeec87dded780330f0abdd5073. Chain 2 (Bitcoin): anchored in block 958448 (2026-07-17T19:49:21Z), 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/BE8MC2400001 — a six-check JSON result.
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0x74df09dbb218ad1be2873bd38cb4927416b6b5e6d8b9bc7b384cb977f7e8ff5b. 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/DEN962100220 — a six-check JSON result.
Nocturne in B Minor, Op. post., Lento con gran espressione (Arr. for Cello and Piano by M. Maisky)
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0x4c44c345a8b9dbff7a6ab915fa4a93e07e3d075b94b48b4d7ea69e86ebdd2194. 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 at https://artists.proofprofile.net/api/v1/bot/ots/verify/track/FRUM72300820 — a six-check JSON result.
24 Préludes, Op. 28: No. 4 in E Minor, Largo (Arr. for Cello and Piano by A. Franchomme) [Adapted by C. Thomas]
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0xade76a00d4d8d706ec08d37e6312fbf0a3884f86b7e47d35a3d3f8abcb8c1003. 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/FRUM72300821 — a six-check JSON result.
Piano Concerto No. 1 in E Minor, Op. 11: II. Larghetto (Arr. for Cello and Piano by J. Brocal and C. Thomas)
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0x8826e733570e6499afd29253d55179f66283775b218f856ae91bdaaa5eae2c34. 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/FRUM72300822 — a six-check JSON result.
Waltz No. 19 in A Minor, KK IVb (Arr. for Cello and Piano by C. Thomas)
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0xfd5939eff9efbd0d0f5cfe4edd459e004cc4b95e4b5a451263f299605ec7c409. 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 at https://artists.proofprofile.net/api/v1/bot/ots/verify/track/FRUM72300823 — a six-check JSON result.
Nocturnes, Op. 15: No. 1 in F Major, Andante cantabile (Arr. for Cello and Piano by A. Franchomme)
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0xa90f99cdfb084d751881370758490428e53048b6f74a3f077413e3eb2e72f196. Chain 2 (Bitcoin): anchored in block 960095 (2026-07-29T11:07:37Z), 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/FRUM72300824 — a six-check JSON result.
Nocturne in C Minor, Andante sostenuto, B. 108 (Arr. for Cello and Piano by C. Thomas)
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0xecb87966d7c82dcb32dfa1388e8107a7736e37b086dd9ad9b17ed7261ca97b35. 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/FRUM72300825 — a six-check JSON result.
17 Polish Songs, Op. posth. 74: No. 2, "Spring" (Wiosna), B.116 (Arr. for Cello and Piano by C. Thomas)
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0x518a2803b2fd24e62cd6a259c832de27ae74cf3ab3948586297bd0ed248e8834. 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/FRUM72300826 — a six-check JSON result.
24 Préludes, Op. 28: No. 15 in D-Flat Major, ''Raindrop'' (Arr. for Cello and Piano by A. Franchomme)
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0x5397681e1afff38c55e30e233c0991e119ad10b019b20c4e44a498d7cec5600d. 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/FRUM72300827 — a six-check JSON result.
4 Mazurkas, Op. 68: No. 2 in A Minor, Lento (Arr. for Cello and Piano by C. Thomas)
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0xcc66e6e7609b5155798836ec1df4424521b3de92734f37930ecae933d87ab8b7. 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/FRUM72300828 — a six-check JSON result.
12 Études, Op. 10: No. 6 in E-Flat Minor (Arr. for Cello and Piano by A. Glazunov)
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0xe52c90cc21bfdaf2b1f2c65d8b66eae6168007acd6d0e1de2070d7f5196f8bbf. 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/FRUM72300829 — a six-check JSON result.
12 Études, Op. 25: No. 7 in C-Sharp Minor (Arr. for Cello and Piano by A. Glazunov)
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0xd36e977d50f5ffe50a9b17e382a657ff7127fe834ce18e9ea12a6c6130f25ad1. 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/FRUM72300830 — a six-check JSON result.
Nocturnes, Op. 27: No. 1 in C-Sharp Minor, Larghetto (Arr. for Cello and Piano by C. Thomas)
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0x68a4a65c22af0d4b87d1900271d44b40ed552f424b7825abb8e22abc78dba5b7. 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/FRUM72300831 — a six-check JSON result.
3 Waltzes, Op. 34: No. 2. in A Minor, Lento (Arr. for Cello and Piano by A. Franchomme)
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0x39ebc2c717b3ec064957487948168ea7dd84bd0ccead241cf2031262ea7e3165. 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/FRUM72300832 — a six-check JSON result.
Nocturne in E Minor, Op. posth. 72 No. 1 (Arr. for Cello and Piano by S. Taneyev)
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0x597657ddefd1467596781d4f21cb7e7a30da1d17890b379b0996986cd7c47a59. 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/FRUM72300833 — a six-check JSON result.
4 Mazurkas, Op. 67: No. 4 in A Minor, Moderato animato (Arr. F. Kreisler) [Adapted for Cello and Piano by C. Thomas]
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0x484cd6da312396c3a15f8a29836105831393d06bc50fcba5aa0f2c1816ffbad4. 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/FRUM72300834 — a six-check JSON result.
24 Preludes, Op. 28: No. 6 in B Minor, Lento assai (Arr. for Cello and Piano by A. Franchomme)
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0x789d1f7d3e9fcedb3a6c9b7a413f18f7fb4fa323a1cdf7846da5b1cac1f20b2f. 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/FRUM72300835 — a six-check JSON result.