Gert Jan Timmerman
 Gert Jan Timmerman (born 15 April 1956) is a Dutch chess player most famous for being the fifteenth ICCF World Champion in correspondence chess 1996–2002.Before becoming the fifteenth World Correspondence Champion he won Final B of the 5th World Cup between 1987 and 1994.He tied for second place behind Mikhail Umansky in a champion of champions tournament the ICCF 50 Years World Champion Jubilee.