The FBI Vault UFO page is the Bureau's official online collection page for released UFO records, sitting inside the FBI's electronic FOIA Library of nearly 7,000 scanned documents and other media.12
The resource matters because it is a direct government source, not a secondary compilation: the page lists 16 related UFO document parts, from UFO Part 01 through UFO Part 16 (Final), and individual part pages provide downloadable PDF files through the Vault viewer.13
For orientation, the FBI's own Vault search summary says the release covers the Bureau's role in UFO reports between 1947 and 1954, when the U.S. Air Force was the primary investigator, the FBI received many reports, and the Bureau worked with the Air Force for a time.4
Read the files as investigative and administrative records, not as confirmed findings. The FBI says the famous March 22, 1950 Guy Hottel memo was an unconfirmed second- or third-hand claim the Bureau never investigated, was not proof of UFOs, and had no reason to be connected to Roswell.5
The broader context is narrow jurisdiction: an FBI podcast says Hoover initially asked agents to help the Air Force sort sightings, but by the early 1950s the Bureau referred flying-saucer reports to the Air Force and its UFO involvement dropped sharply after the Air Force took over.6
Limitations for readers are built into the format. The Vault is a FOIA reading room with search and alphabetical browsing rather than a full research guide, and the FBI's FOIA/Privacy Act exemptions page shows why released records can include redactions or omitted information.278