Verify a sealed document
Paste a sealed export below. This confirms whether the document is byte-identical to the one issued by Blackout Intelligence, and identifies which findings changed if any have. No account, no sign-in — anyone holding the file can check it.
It checks the provenance too — the record of which sources were consulted, what each of them said, and which refused. That is the half that makes an absence mean anything: “nothing found” over three sources of twelve is a different claim from the same sentence over twelve of twelve, and both are inside the signature.
What a valid seal proves
That the findings, their confidence values, their order and any withheld values are exactly as issued, at the time stated. Each finding carries its own hash, so a single altered value is located precisely rather than invalidating the whole file.
What it does not prove
That the underlying information is correct. Integrity and accuracy are different questions. A sealed document faithfully reproduces what the sources said at collection time; assessing whether those sources were right remains the analyst’s job — which is why every finding in a Blackout report carries its own source grading.
Why not just a checksum
Because an unkeyed hash protects against accidents, not against people. Anyone who edits a document can recompute its checksum. These seals are signed with a key held only on our servers, so a recipient can verify a document but cannot forge one.
How to check a document you have been sent
- Ask whoever sent you the report for its sealed export — a JSON file produced by the same lookup. A PDF is a rendering of that file and cannot itself be machine-checked, so the PDF alone is not enough.
- Paste the whole file into the box above. Nothing is uploaded to an account and no sign-in is required.
- Compare the reference and the issue time shown against the ones printed on the document you were given. A valid seal for a different document tells you nothing about the one in your hand.
If verification fails
A failure is not proof of bad faith, and it is worth establishing which kind you have before treating it as one. The common causes are ordinary: the file was copied out of an email client that reflowed it, only part of the export was pasted, or the document was edited after issue for a legitimate reason such as redacting a third party. The console names the specific findings that no longer match, so ask for the original export and compare. A document that still fails on a clean copy is one whose contents cannot be attributed to Blackout Intelligence, and should be treated as unsourced.
Who uses this
Banks and payment providers checking a customer’s onboarding file, insurers and underwriters reviewing a broker’s submission, solicitors receiving disclosure from the other side, and procurement teams handed a supplier assessment they did not commission. In each case the reader has good reason to want the document checked and no relationship with the platform that produced it, which is why verification is public and free.
Programmatic use
POST /api/verify with { seal, cards, collection } taken straight from the export. Unauthenticated, same result. Omit collection and the provenance is reported as unexamined rather than verified.