Leoninus may refer to: Léonin (fl. 1150s—? 1201), the first known significant composer of polyphonic organum Elbertus Leoninus (1519 or 1520–1598), Dutch jurist and statesman who helped negotiate th
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 0xc8a3211b1bc0357a7762d532e2b2531fd3d30186956e653d22e24007eddb4835. Chain 2 (Bitcoin): anchored in block 953885 (2026-06-16T04:12:47Z). Bridge: the canonical record inside this Bitcoin proof contains the same CopyrightID. Verify: download https://artists.proofprofile.net/proofs/artist/0c4c6763-942f-4cc4-bcd8-a2ce91f2021a.json and https://artists.proofprofile.net/proofs/artist/0c4c6763-942f-4cc4-bcd8-a2ce91f2021a.ots, run `ots verify -f record.json proof.ots` (https://opentimestamps.org).
Magnus liber organi de graduali et antiphonario pro servitio divino: Procurans odium
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 0x7903dcc3de8f697c7ebbd0dce8eca41824556cb426a4942416f772c24d71307c. Chain 2 (Bitcoin): anchored in block 960236 (2026-07-30T09:37:10Z), 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 via https://artists.proofprofile.net/api/v1/bot/ots/verify/track/DEAR42466126.
Magnus liber organi de graduali et antiphonario pro servitio divino: Mundus vergens
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0x76dd40d72fcafdd077676a8a2ab6b48fdd4098b151e76f060f7b8ef0ac2499b4. Chain 2 (Bitcoin): anchored in block 960403 (2026-07-31T13:04:34Z), 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 via https://artists.proofprofile.net/api/v1/bot/ots/verify/track/DEAR42466385.
Magnus liber organi de graduali et antiphonario pro servitio divino: Deus misertus hominis
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0xe4d2b729dc3e0eca0c73425d7a53fc30f3cf70b8e1a7d09dbad12a095bc56dde. 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/DEAR42467481.
Magnus liber organi de graduali et antiphonario pro servitio divino: Alleluia Nativitas
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0x27af3909afc730e1be64dd653200c21cf81a5415a1354b3efa58fd977d707646. 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/DEAR42466262.
Magnus liber organi de graduali et antiphonario pro servitio divino: Ave virgo virginum
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0xf81fea6f57ce005058a9baad87befaf1ca1b7754f6dbb30edd30a94f714afb93. 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 via https://artists.proofprofile.net/api/v1/bot/ots/verify/track/DEAR42466173.
Magnus liber organi de graduali et antiphonario pro servitio divino: Sederunt principes
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0x4a701bf03059e8eefede0d1188294785e6bee2b8cd344bd560bb70c71d7933f7. 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/DEAR42466288.