Van Gelder is a Dutch toponymic surname meaning "from/of Guelders", a county and later duchy in the Low Countries.Gelder, van at the Database of Surnames in The Netherlands. People with the name inclu
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 0x0b115212d640431e1a9cfb0b6849b50b682e734d13691edf2f93b787019d4240. Chain 2 (Bitcoin): anchored in block 953772 (2026-06-15T10:33:29Z). Bridge: the canonical record inside this Bitcoin proof contains the same CopyrightID. Verify: download https://artists.proofprofile.net/proofs/artist/c51a13db-e7bd-4fc4-9088-b6c1455416ea.json and https://artists.proofprofile.net/proofs/artist/c51a13db-e7bd-4fc4-9088-b6c1455416ea.ots, run `ots verify -f record.json proof.ots` (https://opentimestamps.org).