Duper may refer to: Duper Sessions, the third album by Norwegian singer/songwriter and guitarist Sondre Lerche Mark Duper (born 1959), former American football wide receiver Super Duper (supermarket
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 0xf52aa28ff4a23834c0eadbe3695c5c7f55bd57d89f84cd2218be6ba135b7c6bf. Chain 2 (Bitcoin): anchored in block 954066 (2026-06-17T08:11:48Z). Bridge: the canonical record inside this Bitcoin proof contains the same CopyrightID. Verify: download https://artists.proofprofile.net/proofs/artist/5f8087f1-a5fa-4334-8a64-5bb9d83eef84.json and https://artists.proofprofile.net/proofs/artist/5f8087f1-a5fa-4334-8a64-5bb9d83eef84.ots, run `ots verify -f record.json proof.ots` (https://opentimestamps.org).