The New Republic and the Galactic Empire were not the only ones to employ interdictors. From 2 BBY, the Black Star Confederacy employed a small, yet potent, interdictor of their own. Extremely rare, the few Predator-class Interdictor Frigates available were usually reserved for the sector fleets guarding the Confederate heartland.
In 17 ABY, the class was upgraded with antimatter reactors and BioComps. In the same year, several Predators were delivered to the Kartanin Warfleet.