Duer is a surname. Notable people with the name include: Alice Duer Miller (1874–1942), American poet Alva Duer (1904–1987), American college basketball coach Carolina Duer (born 1978), Argentine
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 0xad82928ef50ddef8e6d25404efe4f9d7bc780b3165e67d23ad9627f596b38582. Chain 2 (Bitcoin): anchored in block 953923 (2026-06-16T09:51:37Z). Bridge: the canonical record inside this Bitcoin proof contains the same CopyrightID. Verify: download https://artists.proofprofile.net/proofs/artist/1c5f8cd8-0b21-4e9e-af33-c12cf3a915d5.json and https://artists.proofprofile.net/proofs/artist/1c5f8cd8-0b21-4e9e-af33-c12cf3a915d5.ots, run `ots verify -f record.json proof.ots` (https://opentimestamps.org).