Detroit ( , ) is the most populous city in the U.S. state of Michigan. It is situated on the bank of the Detroit River across from the Canadian city of Windsor, Ontario. It is the 26th-most populous
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 0xc3d3b8db7132ca584a80a6829d7318bf6ca463c5f1dcd05963feb93111f775ec. Chain 2 (Bitcoin): anchored in block 953932 (2026-06-16T11:10:43Z). Bridge: the canonical record inside this Bitcoin proof contains the same CopyrightID. Verify: download https://artists.proofprofile.net/proofs/artist/1f44a984-35de-4695-aa81-de8972ebd03b.json and https://artists.proofprofile.net/proofs/artist/1f44a984-35de-4695-aa81-de8972ebd03b.ots, run `ots verify -f record.json proof.ots` (https://opentimestamps.org).