Daniel Deffayet (May 23, 1922 – December 27, 2002) was a French classical saxophonist. He was the professor of saxophone at the Conservatoire de Paris where he succeeded Marcel Mule after Mule's retir
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 0xe2fbfc3fc8afb544acee771f4a4e0894ff436da872beac0e2bc27eb0771b5247. Chain 2 (Bitcoin): anchored in block 953423 (2026-06-12T21:20:00Z). Bridge: the canonical record inside this Bitcoin proof contains the same CopyrightID. Verify: download https://artists.proofprofile.net/proofs/artist/3560058d-9641-4423-ba2b-17ccebb40192.json and https://artists.proofprofile.net/proofs/artist/3560058d-9641-4423-ba2b-17ccebb40192.ots, run `ots verify -f record.json proof.ots` (https://opentimestamps.org).
20th Century Music for Saxophone & Piano
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 0x6fa2287efbd8f2316835e093de466a65011967ac818c797aa31ea26b02f30607. 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/DES805802694.
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0xe9640d5bae4f17d162ff1be96f877814e03e3587445a01923a87d08d3d959793. Chain 2 (Bitcoin): anchored in block 957124 (2026-07-08T03:53:27Z), 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/DES805802696.