thumb|Egidius Quartet at TEDxAmsterdam 2014 The Egidius Kwartet is a Dutch vocal ensemble specialising in the music of the Franco-Flemish school, in particular of the Habsburgs, Margaret of Austria, g
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 0xd16737254e2addc74fb946a8b8cd78eb819000f5bffa626c8c0a45648c21cdb2. Chain 2 (Bitcoin): anchored in block 954066 (2026-06-17T08:11:48Z). Bridge: the canonical record inside this Bitcoin proof contains the same CopyrightID. Verify: download https://artists.proofprofile.net/proofs/artist/3ad8b12e-4ef1-4c40-bf5e-dc58540afb91.json and https://artists.proofprofile.net/proofs/artist/3ad8b12e-4ef1-4c40-bf5e-dc58540afb91.ots, run `ots verify -f record.json proof.ots` (https://opentimestamps.org).
Lassus: Biographie musicale, Vol. 3 (La gloire musicale de la Bavière, le temps des conflits)
Thomas Crecquillon, Fortune Helas, Chansons
The songbook of Hieronymus Lauweryn van Watervliet, 25 Dutch songs
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 0x4b1a95189db0e61b2756cb7b4ab5eed7409cdd10ee158a5ae0f49fb8ec779a03. 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/FR0O70771370.
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0xfbfaa3e716982817a5f30cb2be25313a6b26ec8c481f31b14098ba357c7e1dbc. Chain 2 (Bitcoin): anchored in block 960410 (2026-07-31T13:50:38Z), 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/FR0O70771550.
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
Agricola & Morales & Arcadelt & Lassus: Lamentatio Jeremiae Prophetae
Lamentatio Jeremiae: Res - Sordes Eius. Zain - Vidisti Domine. Caph - Defecerunt
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0xc6114c18a33771fc42834b1e5c79f5ed9489ed2c99a8f0dd473950e5739f6930. 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/NLHR51003375.
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0xaa8686f2b859f0c1788b1c6c854b6d73f73785b01a68dab983658954f928438d. Chain 2 (Bitcoin): anchored in block 960150 (2026-07-29T21:51:49Z), 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 via https://artists.proofprofile.net/api/v1/bot/ots/verify/track/NLHR51003371.
Lamentationes Jeremiae Prohetae, Feria Quinta in Coena Domini: Lamentatio Prima Primi Diei
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0x8886a7fceddb4ac859ececc78e9b387939327cb73e7568afa56fa5b0188a5d71. Chain 2 (Bitcoin): anchored in block 960500 (2026-08-01T03:13:03Z), 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/NLHR51003379.
Leal Amour, Flemish Composers at the Court of Philip II
Payen & Canis & Crecquillon & Des Prez: Tota Vita, Music for Charles V
De Leidse Koorboeken, Vol. III (The Leiden Choirbooks, Vol. III)
De Leidse Koorboeken, Vol. II (The Leiden Choirbooks, Vol. II)
Gheerkin de Hondt, A portrait, Complete motets & chansons
Ronsard et les Néerlandais, and the composers of the Low Countries
Tota Vita, Music for Charles V by Canis and Payen
VIII Festival de Música Barroca "Misiones de Chiquitos" Vol. 1