The rule of res sub judice as provided in Section 10 of Civil Procedure Code

Section 10 CPC - Stay of suit—No Court shall proceed with the trial of any suit in which the matter in issue is also directly and substantially in issue in a previously instituted suit between the same parties, or between parties under whom they or any of them claim litigating under the same title where such suit is pending in the same or any other Court in India have jurisdiction to grant the relief claimed, or in any Court beyond the limits of India established or continued by the Central Government  and having like jurisdiction, or before the Supreme Court Explanation—The pendency of a suit in a foreign Court does not preclude the Courts in India from trying a suit founded on the same cause of action.