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 0x4d96061cf9acc64d335e7c22d497c7a4eb915e9bc45031cb2e2ef8507ef8641f. Chain 2 (Bitcoin): anchored in block 953592 (2026-06-14T05:36:59Z). Bridge: the canonical record inside this Bitcoin proof contains the same CopyrightID. Verify: download https://artists.proofprofile.net/proofs/artist/06f371a1-2e08-4832-930a-b29d4ca5a423.json and https://artists.proofprofile.net/proofs/artist/06f371a1-2e08-4832-930a-b29d4ca5a423.ots, the client at https://opentimestamps.org runs `ots verify -f record.json proof.ots`.
Rachmaninov, Gubaidulina, Tchaikovsky, Scriabin
A:4 Allegro di molto (1st movt from Sonata in F minor, Wq. 63/6)
Piano Exam Pieces 2025 & 2026, ABRSM Grade 7
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 0x78d0b9a490794d101ac4f71fd08fde4825efdae535b33a944dbaac44be0124bf. Chain 2 (Bitcoin): anchored in block 960179 (2026-07-30T00:39:11Z), 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/GBEYQ2457604 — a six-check JSON result.
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0x49dd99e52c02bbaeffe4abfe17710228fbe3f45ecf0d7b5b445c6886c7f2f060. Chain 2 (Bitcoin): anchored in block 960225 (2026-07-30T08:04:30Z), 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/GBEYQ2457611 — a six-check JSON result.
Piano Exam Pieces 2025 & 2026, ABRSM Grade 5
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0xcd7fe0d026042c94254f306f0a17712c243b1bc5017ba61bbba489c54a57a814. Chain 2 (Bitcoin): anchored in block 959114 (2026-07-22T08:41:42Z), 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/GBEYQ2455205 — a six-check JSON result.
A:15 Theme, Var. 1 and Var. 5 (from 12 Variations on "Ah vous dirai-je, maman", K. 265)
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0x9f9617267168548423e611de59ae59ab866e133e440fcb7d39dc30c6ecc9619b. 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/GBEYQ2455215 — a six-check JSON result.
A:11 Allegro in C (No. 2 from Six pièces très faciles, Op. 52)
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0x2475d2299ac9b6c3b46042a8dbdfdeb8a0b1ed16dc8c0c50e2a9a4570f0abc14. Chain 2 (Bitcoin): anchored in block 960105 (2026-07-29T12:35:17Z), 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/GBEYQ2455211 — a six-check JSON result.
A:9 Moderato (1st movt from Sonata in E, Hob. XVI:31)
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0xdb71f9be80abfbda1c3e7765745a66743d77444c19beabefcdb6013d807ee6c3. Chain 2 (Bitcoin): anchored in block 960264 (2026-07-30T14:36:16Z), 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/GBEYQ2457609 — a six-check JSON result.
A:5 Allegro assai (1st movt from Sonatina in F, Anh. 5 No. 2)
Piano Exam Pieces 2025 & 2026, ABRSM Grade 4
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0xd132d5e3683f73b54dc056a2870f77cbff425ce86908f4670e89df048ac3b6eb. Chain 2 (Bitcoin): anchored in block 960125 (2026-07-29T15:38:18Z), 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/GBEYQ2454505 — a six-check JSON result.
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0x779fc162f6351c23f105486693fc6af33b89cd8899c34b4654ed30c51896c90c. Chain 2 (Bitcoin): anchored in block 960144 (2026-07-29T21:09:47Z), 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/GBEYQ2454512 — a six-check JSON result.
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0x9bee3bbee2a6d3b9f9ab9351fb454a0d395536049c7385d1f063536cf8a3e033. Chain 2 (Bitcoin): anchored in block 957064 (2026-07-07T16:43:08Z), 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/GBEYQ2454522 — a six-check JSON result.
Piano Exam Pieces 2025 & 2026, ABRSM Grade 6
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0x200aa737a6866a61c821be249a6a70ca3fc9d17b5084f3a55e3a3870a5ac0a5c. Chain 2 (Bitcoin): anchored in block 959105 (2026-07-22T06:33:30Z), 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/GBEYQ2456906 — a six-check JSON result.
A:7 Allegro (1st movt from Sonata No. 6 in G)
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0xb9e1864dcdc27196d62fa3a429236a78eed7246b6568adf2ab6d77e3dc1a46ee. Chain 2 (Bitcoin): anchored in block 957055 (2026-07-07T15:12:44Z), 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/GBEYQ2456907 — a six-check JSON result.
A:9 Finale: Allegro molto (4th movt from Sonata in G, Hob. XVI:6)
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0xb05635dbf0d37d4c1c4a9454eaafe89033bed0b3e21e1e9d55961dade472671b. 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/GBEYQ2456909 — a six-check JSON result.
Piano Exam Pieces 2021 & 2022, ABRSM Grade 4
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0x2daf59706d29de6e9435ca52f08282e09b1641d89d7e8fee3a4b01125f4d1066. Chain 2 (Bitcoin): anchored in block 960397 (2026-07-31T12:24:41Z), 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/GBEYQ2030909 — a six-check JSON result.
A:13 Andante grazioso and Vars. 1–6 (1st movt from Sonata in A, K. 331)
Piano Exam Pieces 2025 & 2026, ABRSM Grade 8
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0x30474a0aacfd8822b184cd959d0b741fc10362c8a870b2eb1667f63191263789. 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/GBEYQ2458313 — a six-check JSON result.
B:12 Impromptu in A flat (No. 2 from Four Impromptus, Op. 142, D. 935)
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0xdf22440aae263777d2e8f837a9508fde4cf26721c9c32b542bf66ddcf3566091. Chain 2 (Bitcoin): anchored in block 959152 (2026-07-22T16:23:52Z), 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 at https://artists.proofprofile.net/api/v1/bot/ots/verify/track/GBEYQ2458328 — a six-check JSON result.