Research help • The guide
A declassified file is usually a scan or a FOIA release.
Here’s how to read one.
The banner at the top and bottom of the page — TOP SECRET, SECRET, CONFIDENTIAL — is the classification the document had. Portion markings — (U), (C), (S) — label individual paragraphs: Unclassified, Confidential, Secret. A DECLASSIFIED stamp with a date is when the document was released, not when it was written.
Read the banner first. It tells you what the document was when it was made — and the declassification stamp tells you when it stopped being secret. The two dates can be decades apart.
The black bars. The code in the margin says why the passage was withheld:
A redaction hides something. It doesn’t prove what it hides. The theorizing about what sits under the black bars belongs in the forum — this site stays with the visible record.
More codes: Glossary — FOIA exemptions
Routing stamps, distribution lists, and file numbers tell you where a document traveled. A file number can find you the same document in another archive — a Blue Book case number, for example, will turn up the same file in the National Archives catalog, the FBI Vault, or a FOIA release, sometimes with different pages redacted in each copy.
When two copies of the same document disagree on what’s blacked out, the less-redacted copy is the one to read — and the difference itself is worth noting.
Check the date, the author, and who it was routed to before the headline claim. One memo is one person’s view, not the government’s conclusion. A cover memo and its attachment can say opposite things. The last page of a file — the distribution list, the forwarding note — sometimes matters more than the first.
Project Blue Book’s record cards sometimes carry an explanation even for the famous cases — and sometimes the file itself disagrees with the card. Read the record, not the legend.
Every document on this site links to its official source — the National Archives catalog, the CIA Reading Room, the FBI Vault, or war.gov/ufo. If a document you find elsewhere has no source, treat it as a rumor until you can place it: which agency wrote it, which archive holds it, and under what file number.
Sources, by agency — where every document on this site comes from.
Project Blue Book closed 12,618 cases. The unexplained ones are the ones with no conventional explanation after investigation. That’s all it means — and it’s enough.
It is not a finding of alien origin. It is a file that stayed open.
What the parts of a declassified page look like, and what each one is telling you. The page below is a diagram, not a real document — the real ones are linked throughout this site.
Declassified • 2026-03-08
(U) MEMORANDUM FOR THE RECORD
(S) Subject: Unidentified aerial phenomena, 14 November 2004
(U) 1. At approximately 1200 local, two F/A-18 aircraft were vectored to intercept an object tracked by the USS Princeton. (b)(1) reported the object as smooth, white, and approximately forty feet in length.
(U) 2. Distribution: (b)(6), UAP Task Force, Office of Naval Intelligence.
The banner says SECRET — the classification the page had when it was written. The stamp says declassified March 8, 2026 — when it was released, not when it was written. The (U) and (S) are portion markings: paragraph 1 is unclassified, the subject line is secret. The black bars carry their reasons in the margin: (b)(1) for a still-classified passage, (b)(6) for a name. The distribution line tells you who read it — and where else to look for copies.
Practice on a real one: the Robertson Panel report and the Durant memorandum, both in the homepage viewer, and the AARO Historical Record Report, Volume I, in Sources — Department of War / AARO.
Stuck on a marking, a stamp, or a redaction code? Ask in the forum’s Research Help category — that’s what it’s for. Post the marking, not the whole document, and someone will walk through it with you. The same guide is pinned there.