thumb|Adrianus Dingeman de Groot Adrianus Dingeman (Adriaan) de Groot (Santpoort,In the municipality of Velsen, according to some sources. 26 October 1914 – Schiermonnikoog, 14 August 2006) was a Dutc
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 0xa1828317d831106d26b6c7272be03e8793e90687b081ff8f2423f3cf7719489a. 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/ae5db80f-d77d-43a8-acd9-b7893d0ed878.json and https://artists.proofprofile.net/proofs/artist/ae5db80f-d77d-43a8-acd9-b7893d0ed878.ots, run `ots verify -f record.json proof.ots` (https://opentimestamps.org).