Istvan Fellner is a Hungarian artist and animator. In the late 1970s he worked for Semic in Sweden as one of the artists of the series 'Flygsoldat 113 Bom' in 91:an magazine. In the 1980s he moved to the United States, where he worked on animated TV series such as 'Dennis the Menace' (based on Hank Ketcham's comic series), 'Tiny Toon Adventures', Matt Groening's 'The Simpsons', Everett Peck's 'Duckman' and also on 'The Wild Thornberrys' and 'Rugrats'. His name is usually anglicized as "Steve Fellner".