Today it proves integrity. If the fingerprint appears in our issuance register, the document has not been modified since it was issued. You get the issue date, the engine version that produced it, and the language.
For the pages we publish ourselves, the check also returns the edition. The calibration page is archived in full at every regeneration, not merely fingerprinted: if the fingerprint you paste belongs to an archived edition, you can download it exactly as published, byte for byte — not just learn that it existed. Documents issued for clients are not archived here: the public register holds nothing about them, and none of their content.
Coming in Q4 2026: the check will also return the inputs — the price curve source and its own fingerprint, the configuration, the price sample — so the document is reproducible, not merely unaltered. Until then we do not claim it does.
It can also be checked entirely without us. Replace the fingerprint in the document footer with @@AMPRENTA-SHA256@@ and recompute SHA-256 over the file. The method is written in every document and does not depend on this server.
We do not keep verified fingerprints. The form submits by POST, so the fingerprint never enters the page address or the server logs, and the request body is not recorded anywhere. We cannot know which document you checked, and we cannot influence the result.
If the fingerprint is not found, there are three explanations the register cannot tell apart: the document was modified after issuance, it was not issued by Voltaraj, or it was issued before the register started. We name all three, because we do not know which one it is.