Ciprian Manolescu from Romania managed to write a perfect paper (42/42) three times.
Reid Barton (USA) was the first participant to obtain a gold medal four times (1998-1999-2000-2001). Christian Reiher (Germany) is the only other participant to have won four gold medals (2000-2001-2002-2003); Reiher also obtained a bronze medal in 1999.
In 1994, all six members of the USA team wrote a perfect paper. This accomplishment was noted in TIME Magazine.
Terence Tao from Australia got a gold medal at the age of thirteen in 1988, being the youngest person to have a gold medal.