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 0x772fab8802e209a0950ac0d0ee2d34f0c27c5365135fdcac17abd8af0d4d0557. Chain 2 (Bitcoin): anchored in block 954346 (2026-06-19T03:51:26Z). Bridge: the canonical record inside this Bitcoin proof contains the same CopyrightID. Verify: download https://artists.proofprofile.net/proofs/artist/99555796-54ca-42b2-8a4e-43afabce2e99.json and https://artists.proofprofile.net/proofs/artist/99555796-54ca-42b2-8a4e-43afabce2e99.ots, run `ots verify -f record.json proof.ots` (https://opentimestamps.org).
Trenc d'alba, from the film by Anna Llargués (Original Motion Picture Soundtrack)
Flight, from "Sola" by Clàudia Orriols (Original Motion Picture Soundtrack)
Triss, from "Egg and Chips" by Helen Iley (Original Motion Picture Soundtrack)
Finale, from "La Indeseada" by Anna Llargués (Original Motion Picture Soundtrack)