thumb|upright=1.3|Choralschola A Choralschola, known simply as schola, is a choir for singing Gregorian chant or plainsong. It consists traditionally of only men, but more recent groups sometimes als
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 0xbfe9992d83f4a20edaa240b456257d0ddd9b02e9c174dc24694b5dcb53d5899a. Chain 2 (Bitcoin): anchored in block 953645 (2026-06-14T14:31:42Z). Bridge: the canonical record inside this Bitcoin proof contains the same CopyrightID. Verify: download https://artists.proofprofile.net/proofs/artist/3ef5ca4b-f6e7-464b-91b0-4c31473d6290.json and https://artists.proofprofile.net/proofs/artist/3ef5ca4b-f6e7-464b-91b0-4c31473d6290.ots, the client at https://opentimestamps.org runs `ots verify -f record.json proof.ots`.
NPR Milestones of the Millennium: CHANT - Hymns and Sequences - Gloria in excelsis Deo
Ut queant laxis (Hymn to St. John the Baptist)
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 0x67c75daef944e1968a2315336a52703ff1f425f5d84fead2649a49e0aa31c327. 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/USSM17800124 — a six-check JSON result.