FOIA deep study · declassified archive
FBI Vault — UFO
Bureau UFO correspondence and case material in the Vault.
FBI Vault UFO sets collect Bureau correspondence, memos, and investigative fragments on flying saucer / UFO reports. Together with NARA’s BLUE BOOK holdings they form the dual public archive for mid-century U.S. UFO bureaucracy.
Educational FOIA index entry. Always verify wording on the official primary PDF.