Section 11 of CPC Res Judicata in Law
No court shall try any suit or issue in which the matter directly and substantially in issue has been directly and substantially in issue in a former suit between the same parties or between parties under whom they or any of them claim, litigation under the same title in a court competent to try such subsequent suit or the suit in which such issue been subsequently raised, and has been heard and finally decided by such court.

Section 11 of the code of Civil Procedure, 1908, embodies the rule of res judicata or the rule of conclusiveness of the judgment, as to the points decided either of facts, or of law, or of facts and law, in every subsequent suit between the same parties.