Koeman is a Dutch occupational surname. Though the name translates as "cow man" in modern Dutch, it is a derivative, via Kooman, of Koopman (= merchant).Koeman name origin at the Meertens Institute da
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 0xb5bab8a8e01fa8f6253f6cfb5ea4381b2deb48e50a930d006bafa1b8ceb62aa1. Chain 2 (Bitcoin): anchored in block 954555 (2026-06-20T12:10:20Z). Bridge: the canonical record inside this Bitcoin proof contains the same CopyrightID. Verify: download https://artists.proofprofile.net/proofs/artist/af22f0b8-79f7-4803-9e6c-1c70e0cb8d38.json and https://artists.proofprofile.net/proofs/artist/af22f0b8-79f7-4803-9e6c-1c70e0cb8d38.ots, run `ots verify -f record.json proof.ots` (https://opentimestamps.org).