Mateo Flecha (Catalan: Mateu Fletxa; 1481–1553) was a Spanish composer born in Kingdom of Aragon, in the region of Prades. He is sometimes known as "El Viejo" (the elder) to distinguish him from his n
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 0xeb0109d652deea841cf4905250b692af6325a0ababc46c7331d9f5d5d9c568b2. Chain 2 (Bitcoin): anchored in block 953795 (2026-06-15T13:44:27Z). Bridge: the canonical record inside this Bitcoin proof contains the same CopyrightID. Verify: download https://artists.proofprofile.net/proofs/artist/e1bf6aee-cba2-4fe4-9df2-1387ee467345.json and https://artists.proofprofile.net/proofs/artist/e1bf6aee-cba2-4fe4-9df2-1387ee467345.ots, run `ots verify -f record.json proof.ots` (https://opentimestamps.org).
Flecha: Cancionero de Uppsala: No. 46, "Riu, riu, chiu, la guarda ribera"
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 0x74bb26ffce8ca59fdea1abda96c44c326515fadb2f7154c84baf321562397a07. 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/GBAYC9803151.
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0xef4e1eb92dd1fc18e32dfa18f45b890297eea45674bc0cec0fe3553f69c6147a. Chain 2 (Bitcoin): anchored in block 957084 (2026-07-07T20:41:57Z), 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/CH4211900992.