Robert Heppener (9 August 1925 in Amsterdam – 25 August 2009 in Bergen), also known as Bob Heppener, was a Dutch composer. He was among the most important Dutch composers of the 20th century. Early l
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 0x19efca9bf818e137ae6b37c2b0360440a6a926a92bc8448418cdbc07f3344cab. Chain 2 (Bitcoin): anchored in block 954342 (2026-06-19T03:22:39Z). Bridge: the canonical record inside this Bitcoin proof contains the same CopyrightID. Verify: download https://artists.proofprofile.net/proofs/artist/90c1f53d-98b4-4af0-84e6-74f0cba3740a.json and https://artists.proofprofile.net/proofs/artist/90c1f53d-98b4-4af0-84e6-74f0cba3740a.ots, run `ots verify -f record.json proof.ots` (https://opentimestamps.org).
Tussen Bomen / Spinsel / Four Songs on poems by Ezra Pound
Robert Heppener: Canti Carnascialeschi, Del Iubilo Del Core Che Esce in Voce, Nachklänge & Bruchstücke Eines Alten Textes
Ligeti: Lux aeterna / Heppener: Im Gestein
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 0x399b959ad1f873fd0eed128aafeb57f8ff231cc77614e0456ff8808d2a74942a. 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/FRZ140715080.
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0x12594393f4604dc0377ea3901937af6a7eb484c2e4209453900ded82fddffa10. 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/FRZ140715090.