The Denver Post reports 6-year-old Veronica Moser-Sullivan's father, Ian Sullivan, filed his lawsuit against Cinemark on Friday in Denver.
Like other lawsuits filed before it, Sullivan's suit argues inadequate security at the Century Aurora 16 allowed the attack to happen.
Veronica was among 12 people killed when a gunman opened fire at a midnight showing of the new Batman movie July 20. The attack also injured at least 58 people.
Cinemark says it couldn't have foreseen the attack.
(Copyright 2012 by The Associated Press. All Rights Reserved.)