PLANO (CBSDFW.COM) – If you’re planning to see a movie at a Cinemark theater this weekend, you might want to check out the company’s new bag policy. Starting on Thursday, the theater chain based in Plano will begin banning large bags from its auditoriums.

According to Cinemark’s new policy, any bags that are bigger than 12 inches by 12 inches by 6 inches will not be allowed into theaters. This is a similar size requirement to the bag policies already being used in many of the nation’s popular arenas and venues — including AT&T Stadium in Arlington.

Diaper bags and medical equipment bags are excluded from the new rules.

The company added that there will not be a general area at their theaters for checking bags and personal belongings, but they do reserve the right to have workers inspect any bags or packages that are entering the building and ask that larger bags not be brought inside.

Cinemark said that this move is to “enhance the safety and security of our guests and employees.”

It was a Cinemark theater in Colorado where 12 people were killed and dozens more were injured during a shooting rampage in 2013, at a midnight screening of “The Dark Knight Rises.” The gunman used an exit door to move weapons in and out of the theater. In court papers, Cinemark called the tragedy “unforeseeable and random.”