The New Dutch Academy (NDA) is an international Dutch Baroque orchestra based in The Hague, the Netherlands. It is composed of 40 international, early music, specialist musicians, who gather in The Ha
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 0x4ad4c48f4ccf66d9a6f023269d3dd8469eca536111177c3998f1dc7f219ebecb. Chain 2 (Bitcoin): anchored in block 954667 (2026-06-21T07:29:20Z). Bridge: the canonical record inside this Bitcoin proof contains the same CopyrightID. Verify: download https://artists.proofprofile.net/proofs/artist/c6e046a1-392f-4c12-916e-f13af78ddba9.json and https://artists.proofprofile.net/proofs/artist/c6e046a1-392f-4c12-916e-f13af78ddba9.ots, the client at https://opentimestamps.org runs `ots verify -f record.json proof.ots`.
Flute Concerto in D Major: II. Andante mezza voce
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 0xdbc071a725f57c17d30b0b5653ac482c93e2e4f4a524c1d3069eec9066f2621d. 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/USX762101714 — a six-check JSON result.
Flute Concerto in D Major: III. Allegro molto
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0x21c802078c4bb89b204d09a00dd91f318b4171b872a256b223b56aa4b432a9f8. 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/USX762101715 — a six-check JSON result.
Arcangelo Corelli: Concerti Grossi (including "Christmas Concerto") & Vivaldi: Lute and Mandolin Concerto
Concerto da Camera in B-Flat Major, Op. 6 No. 11: I. Preludio – Andante – Largo
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0x2b1163846ba0f52bf7372744cdff2bb0189cf76d9ad6a02dc851fd7dcc3776a2. Chain 2 (Bitcoin): anchored in block 960285 (2026-07-30T17:26:40Z), 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/USX762205101 — a six-check JSON result.
Concerto da Camera in B-Flat Major, Op. 6 No. 11: II. Allemande
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0xd0342b6a85ee88fb92f8c58fd21f1cf9b88d8cf107ea6a45d4a22739eaf487d7. 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/USX762205102 — a six-check JSON result.
Concerto da Camera in B-Flat Major, Op. 6 No. 11: III. Adagio – Andante – Largo
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0x353281dad30f265f367be5ca837eb72267af49b4b78fb9d3513f220d543206a1. 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/USX762205103 — a six-check JSON result.
Concerto da Camera in B-Flat Major, Op. 6 No. 11: IV. Sarabanda
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0x829c0b792d40b70ab3f2743e5ad3b29337ca672311813e1d8bcaaceef6db728d. 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/USX762205104 — a six-check JSON result.
Concerto da Camera in B-Flat Major, Op. 6 No. 11: V. Giga
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0x011b6384b62c6313bac1ae5ba4fd10dcc9815d4549731c51e7b226769505e301. Chain 2 (Bitcoin): anchored in block 960337 (2026-07-31T02:51:48Z), 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/USX762205105 — a six-check JSON result.
Sonata a 4 in G Minor, WoO 2: II. Allegro
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0xdd07f5fdfbbcc959b90b7827d6f243b45bc5f60c5622336d913529bed89dd06c. 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/USX762205107 — a six-check JSON result.
Sonata a 4 in G Minor, WoO 2: III. Grave – Presto
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0xcaff67ee61f4ce1ec10b9a2b7c6913541b278e2d34c020be18de8dcde54efbf9. 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/USX762205108 — a six-check JSON result.
Sonata a 4 in G Minor, WoO 2: IV. Vivace
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0x9ff106564945a2e4bdbbe8d21c476c52ec29e7f1dd34420e7ea6d8bd303a8fea. 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/USX762205109 — a six-check JSON result.
Concerto da Camera in F Major, Op. 6 No. 12: I. Preludio – Adagio
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0x20952d0388224a722b3ff40a785e503c55ab5fe87081b56cbb6fc22dd9cd4710. Chain 2 (Bitcoin): anchored in block 960389 (2026-07-31T10:20:10Z), 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/USX762205110 — a six-check JSON result.
Concerto da Camera in F Major, Op. 6 No. 12: II. Allegro
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0xc0c58875f9309ea8324bf0fe9afda742bc17194f1fabd7f9993574749fd85011. 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/USX762205111 — a six-check JSON result.
Concerto da Camera in F Major, Op. 6 No. 12: III. Adagio
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0xf2d546da8c49371a9a9115db272e73284c45569d5ee1910c9ccaad6f7ad434e8. Chain 2 (Bitcoin): anchored in block 960463 (2026-07-31T20:42:35Z), 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/USX762205112 — a six-check JSON result.
Concerto da Camera in F Major, Op. 6 No. 12: IV. Sarabanda
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0x5e74255b83c98e0fefd270fdd123f38a944aea7d2d2d10ff6b28cdf05fffec40. Chain 2 (Bitcoin): anchored in block 960497 (2026-08-01T02:22:04Z), 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 at https://artists.proofprofile.net/api/v1/bot/ots/verify/track/USX762205113 — a six-check JSON result.
Concerto da Camera in F Major, Op. 6 No. 12: V. Giga
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0xb8e059592d77fde6b28fb4dda5a65a59af40f52f7bee745223c0a1bb42b59eac. Chain 2 (Bitcoin): anchored in block 960468 (2026-07-31T21:25:57Z), 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 at https://artists.proofprofile.net/api/v1/bot/ots/verify/track/USX762205114 — a six-check JSON result.
Concerto da Chiesa in D Major, Op. 6 No. 4: I. Adagio – Allegro
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0x0f262137817d25e717ca916ca2b8516ac85ead9ab82d902c4d375b51db1467d7. 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/USX762205115 — a six-check JSON result.
Concerto da Chiesa in D Major, Op. 6 No. 4: II. Adagio – Vivace
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0x1ed36d5db53a37b9405d5ee9822d4ced23788b70e446fe15e5ea4ad25dd8bc10. 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/USX762205116 — a six-check JSON result.
Concerto da Chiesa in D Major, Op. 6 No. 4: III. Allegro
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0x415a9f36f122b6e2f7c0cdbf690622bb0d4957d4382430d2b5d4386b6a9795f4. 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/USX762205117 — a six-check JSON result.
Concerto da Chiesa in G Minor, Op. 6 No. 8 "Fatto per la Notte di Natale / Christmas Concerto": I. Vivace – Grave
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0xf35ec18fb8f66bf63a4d720d2dff92f20923753b2fa4a52244a02234c91a94f9. Chain 2 (Bitcoin): anchored in block 960487 (2026-08-01T00:15:43Z), 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/USX762205118 — a six-check JSON result.
Concerto da Chiesa in G Minor, Op. 6 No. 8 "Fatto per la Notte di Natale / Christmas Concerto": II. Allegro
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0x499f9e6bccda394574ff66239016888967ff7255b2fb0ca031dbb2785067a119. 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/USX762205119 — a six-check JSON result.
Concerto da Chiesa in G Minor, Op. 6 No. 8 "Fatto per la Notte di Natale / Christmas Concerto": III. Adagio – Allegro – Adagio
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0xffe76085a73130b6ffdbb31b635b2e06759e5852d1c3756a67e97dd6614cd212. Chain 2 (Bitcoin): anchored in block 960321 (2026-07-30T22:27:30Z), 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/USX762205120 — a six-check JSON result.
Concerto da Chiesa in G Minor, Op. 6 No. 8 "Fatto per la Notte di Natale / Christmas Concerto": IV. Vivace
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0x95a9199cef53c06ba86461f40130169d3d19e8f16de6e849bb8a865d04cd452f. 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/USX762205121 — a six-check JSON result.
Concerto da Chiesa in G Minor, Op. 6 No. 8 "Fatto per la Notte di Natale / Christmas Concerto": V. Allegro – VI. Pastorale
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0xecf970d5ac4a1b47b7597614871ffa234d029f5b40412eb2139ef1971d13a7d5. 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/USX762205122 — a six-check JSON result.
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0x802236f5622c12ae7dd05c30693685f10599933ca1e1445de9637a2cb31b7a76. Chain 2 (Bitcoin): anchored in block 960441 (2026-07-31T17:29:52Z), 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/USX762205123 — a six-check JSON result.
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0x6f06bfd2e402f7086e8c8c7f5b4783c84aa69f29a5a6a1d55f1167a2bd64301e. 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/USX762205124 — a six-check JSON result.
Lute Concerto in D Major, RV 93: II. Largo
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0xb511ff01a11c40db51608651d0eb836c5e14dbc7e648142548519c7912574fc1. 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/USX762205125 — a six-check JSON result.