thumb|As a TV actor in De schaduw van een revolverman, 1964 Catharina Anna Petronella Antonia "Kitty" Courbois (13 July 1937 – 11 March 2017) was a Dutch actress. In 2010 she was awarded the Medal of
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 0x591c095bef718a3b81850301939815fad7da8b36ab84d7b8a1935e2a46ef3088. Chain 2 (Bitcoin): anchored in block 954097 (2026-06-17T13:13:51Z). Bridge: the canonical record inside this Bitcoin proof contains the same CopyrightID. Verify: download https://artists.proofprofile.net/proofs/artist/7b403d20-12a3-4a23-8f99-7c34692b781c.json and https://artists.proofprofile.net/proofs/artist/7b403d20-12a3-4a23-8f99-7c34692b781c.ots, the client at https://opentimestamps.org runs `ots verify -f record.json proof.ots`.