Jaap Schröder (31 December 1925 – 1 January 2020)Dutch violinist and musicologist Jaap Schröder dies aged 94 was a Dutch violinist, conductor, and pedagogue. He studied at the Amsterdam Conservatory
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 0x57da4876920f87784865f4b6f95e1248b1d519b6cd0439ba4d4ea9cc5ad462f6. Chain 2 (Bitcoin): anchored in block 953407 (2026-06-12T19:24:56Z). Bridge: the canonical record inside this Bitcoin proof contains the same CopyrightID. Verify: download https://artists.proofprofile.net/proofs/artist/8e6b497a-70a5-40f1-b055-dde44688541f.json and https://artists.proofprofile.net/proofs/artist/8e6b497a-70a5-40f1-b055-dde44688541f.ots, the client at https://opentimestamps.org runs `ots verify -f record.json proof.ots`.
Concerto for 2 Violins, Strings, and Continuo in D minor, BWV 1043: 2. Largo ma non tanto
The World of The Academy of Ancient Music
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 0x7b3f511b37143ef269cd7d19293204908b4fea21a7cc35c461cdac1f48bd5f51. Chain 2 (Bitcoin): anchored in block 959123 (2026-07-22T11:35:32Z), 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/GBF078100122 — a six-check JSON result.
Symphony No. 35 In D, K.385 "Haffner": 4. Finale (Presto)
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0xb8ee4e558b8d2715cdbfbf8c43674e37dc5b6fb7b0472b561be0019682c30f97. Chain 2 (Bitcoin): anchored in block 957075 (2026-07-07T18:50:38Z), 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 at https://artists.proofprofile.net/api/v1/bot/ots/verify/track/GBF077913065 — a six-check JSON result.