Geert Chatrou is a professional whistler from the Netherlands. Early life Chatrou was born in Sint Odiliënberg in 1969. He started whistling at the age of four inspired by his father who used to whis
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
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0x3afc885a1e336965cb21d2652d9a3531c2091bf7bad728e41ad3d8d09b146090. 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/3e1aa17e-a007-49b8-88c5-6320d7ae6e78.json and https://artists.proofprofile.net/proofs/artist/3e1aa17e-a007-49b8-88c5-6320d7ae6e78.ots, run `ots verify -f record.json proof.ots` (https://opentimestamps.org).