"Controversy Erupts Over Inclusion of "Jeff" on Nuclear Superpowers List"
A graphic by CNN based on data from the Federation of American Scientists listed "Jeff" as the tenth biggest possessor of nuclear weapons, causing confusion and concern. However, "Jeff" is not a person but an acronym for Joint Evaluated Fission and Fusion Project, an international collaboration to create a library of nuclear data. This was likely a data mishap, and Jeff does not actually possess nuclear weapons.