As per case facts, plaintiffs filed a suit for declaration of title and permanent injunction, which was decreed ex parte by the Trial Court. A third party, Ajay Sidara, who ... later purchased the suit property from a previous transferee of the original defendant, challenged this decree in the First Appellate Court, arguing non-impleadment and lack of opportunity to be heard. The First Appellate Court allowed Sidara's appeal, setting aside the decree and remanding the case for fresh adjudication due to non-joinder of necessary parties. The plaintiffs then filed this appeal against the remand order. The question arose whether a non-party could appeal an ex parte decree and if the remand based on non-joinder of necessary parties was justified. Finally, the Court affirmed that an aggrieved non-party can appeal. It held that the First Appellate Court was correct in remanding the case under Order 41 Rule 23-A CPC, as the suit was instituted against a defendant who had already divested title, making the subsequent transferees (Harsha Rana and Ajay Sidara) necessary parties. Their non-impleadment was a fundamental defect, rendering the original decree vulnerable and warranting a fresh adjudication with all parties present.