Town bosses are forced to keep their supporters seated under Football Licensing Authority regulations or face the capacity of Portman Road being reduced.
Should supporters not obey the rules that are set out by the FLA, Town could use a range of punishments on their supporters, including, but not limited to a ban from attending further games at the ground.
Speaking of the situation, a club spokesman confirmed: "We have sent out a significant number of letters to supporters who have been identified as those who persistently stand, bringing to their attention that it breaches the stadium's by-laws.