Farbauti or Saturn XL (also called S/2004 S 9) is a moon of Saturn. It was found by Scott S. Sheppard, David C. Jewitt, and Jan Kleyna on December 12, 2004. Farbauti was found using the Mauna Kea Observatory and is the 40th moon from Saturns surface. The public did not know about Farbauti until May 4, 2005.