Abigail Fischer is an American mezzo-soprano. Fischer is known for her commitment to contemporary music, having premiered works by composers Missy Mazzoli, John Zorn, Nico Muhly and Elliot Carter. S
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 0x8013b20494596077453acdd042283c85d8cc1b88e0fb3c9124e34dc688a928f7. Chain 2 (Bitcoin): anchored in block 954115 (2026-06-17T15:44:10Z). Bridge: the canonical record inside this Bitcoin proof contains the same CopyrightID. Verify: download https://artists.proofprofile.net/proofs/artist/76b1b90c-821e-4e52-9813-ae2b1a97b1c7.json and https://artists.proofprofile.net/proofs/artist/76b1b90c-821e-4e52-9813-ae2b1a97b1c7.ots, run `ots verify -f record.json proof.ots` (https://opentimestamps.org).
Missa in Angustiis "Lord Nelson Mass": I. Kyrie
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 0xaddae9542e0321f8149a8e884a4e066fea137dd993924cef69eb47067d9f31ad. Chain 2 (Bitcoin): anchored in block 956312 (2026-07-02T05:09:12Z), 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/GBASH1342601.
Missa in Angustiis "Lord Nelson Mass": II. Gloria
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0x60e3fdae51f7f2d9cd0746c48fdf5549b7eba839fa870be449646111413817e4. 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 via https://artists.proofprofile.net/api/v1/bot/ots/verify/track/GBASH1342602.
Missa in Angustiis "Lord Nelson Mass": VI. Et incarnatus
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0xeb83f0c5bfa0ff4a9aba6c151d12cf3102a6eb5390da60a924d70573a32d0cfd. Chain 2 (Bitcoin): anchored in block 956349 (2026-07-02T11:34:59Z), 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 via https://artists.proofprofile.net/api/v1/bot/ots/verify/track/GBASH1342606.
Missa in Angustiis "Lord Nelson Mass": VIII. Sanctus
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0xeb597586a3a6fc40e18128d64f385c9f915909eb48d113eb4ee5b73257e2e8a8. Chain 2 (Bitcoin): anchored in block 956894 (2026-07-06T07:53:57Z), 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 via https://artists.proofprofile.net/api/v1/bot/ots/verify/track/GBASH1342608.
Missa in Angustiis "Lord Nelson Mass": X. Agnus Dei
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0x323f94b42d086dbcb2ee61347c42dc723a3eba1f159f8c3b0a4be462864d82f7. Chain 2 (Bitcoin): anchored in block 957061 (2026-07-07T16:07:00Z), 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/GBASH1342610.
Symphony No. 102 in B-Flat Major: IV. Finale
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0xd4d8986f0e47a65df7f698d6bca99e3bbbf7e8e8e9829c15dae524210f21b76c. Chain 2 (Bitcoin): anchored in block 957145 (2026-07-08T08:56:20Z), 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/GBASH1342615.
Missa in Angustiis "Lord Nelson Mass": IV. Quoniam
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0x48fbfb560f92e8ae207db191c021fe638f22f5a6533cf60dc4c38d6072bec1ee. 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 via https://artists.proofprofile.net/api/v1/bot/ots/verify/track/GBASH1342604.
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
Missa in Angustiis "Lord Nelson Mass": IX. Benedictus
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0xe48a43382c6e1336b4d06313750a4a3bda273c821d5e6b714341ddbe42ce592b. Chain 2 (Bitcoin): anchored in block 960095 (2026-07-29T11:07:37Z), 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/GBASH1342609.
Harold Meltzer: Variations on a Summer Day and Piano Quartet