Open Fuel Standard Act of 2009 or the OFS Act - Requires each light-duty automobile manufacturer's annual covered inventory to comprise at least: (1) 50% fuel choice-enabling automobiles in years 2012-2014; and (2) 80% fuel choice-enabling automobiles in 2015, and in each subsequent year.
Defines "fuel choice-enabling automobile" as: (1) a flexible fuel automobile capable of operating on gasoline, E85, and M85; or (2) an automobile capable of operating on biodiesel fuel.
Authorizes a manufacturer to request an exemption from such requirement from the Secretary of Transportation.