Culver's Corp. is evaluating the possible need for a policy addressing handguns in its restaurants.
The issue came to light after an incident at the East Towne Culver's on Saturday evening.
Five members of the open-carry advocacy group, Wisconsin Carry, met to eat dinner and socialize. The men were all legally openly carrying firearms.
"They started to notice a police presence was gathering around the building so they suspected that somebody had called the police regarding them because they had firearms," said Auric Gold, the group's secretary.
Madison police confirmed that a call was placed to them by a concerned woman who had seen the men in the restaurant.
"She sees some of these people with guns on their hips, and she's concerned enough to call us saying she feels that if she doesn't call and something horrible happens, she would feel terrible that she didn't call," said Joel DeSpain, Madison Police Department spokesman.