The main legal point established in the judgment is the application of res judicata and the requirements for adverse possession between co-owners, as well as the limitations on a co-owner's ability to claim value of improvements without authorization from other co-owners.

S. Padmanabhan, J.

1. Second appeal is by the defendant. Suit is one for partition. Respondent plaintiff is his direct brother. They are admittedly joint lessees entitled to the suit property in equal halves. The appellant's contentions are:

a) the suit for partition is not maintainable because of an oral partition of 1949, by which he is in separate possession as full owner;

b) if not, the title of the respondent in the property in his possession is lost by adverse possession; and

c) if the above two contentions are not accepted, he is entitled to value of improvements.

2. Trial court rejected the pleas of oral partition and adverse possession. These findings were confirmed in appeal. Claim for value of improvements was allowed by the trial court. Allowing the cross objection filed by the respondent, the claim for value of improvements was turned down by the appellate court. But a direction was made that, as far as possible, the property in the possession of the appellant will be allotted to his share without valuing the improvements effected by him. Separate possession pleaded by the appellant was accepted by both the courts below. That factual finding must be treated as final and conclusive.

3. The finding against oral partition also is beyond interference. It is not only a conclusion in the absence of sufficient evidence, but the result of a successful plea of res judicata also. O. S. No. 761 of 1966 was filed by the jenmi for realisation of rent of the entire premises. Appellant was the first defendant and respondent was the second defendant. Appellant pleaded oral partition and said that he is liable only for the proportionate rent for the premises in his possession. Respondent denied the oral partition. Both were necessary parties to that suit. Claim of the jenmi was on the original lease to get the entire rent from both the tenants jointly and severally charged 3 on the entire premises. In order to consider and allow or reject that claim, a decision on the conflict between the defendants regarding oral partition was necessary. That was decided, as Exts. A9 and 10 judgment and decree show. The oral partition was found against and the relief claimed by the plaintiff was granted. Claim of the appellant is that Exts. A9 and 10 will not operate as res judicata.

4. Various decisions, including Sheoparsan Singh and others v. Ramandan Prasad Narayan Singh and others (AIR 1916 PC 78). Mt. Munni v. Tirloki Nath (AIR 1931 PC 114), Kishun Prasad Pandey and others v. Durga Prasad Thakur and others (AIR 1931 PC 231), Maung Sein Done v. Ma Pan Nyun (AIR 1932 PC 161), Kedar Nath v. Munshi Ram (AIR 1935 PC 139). Syed Mohammad Saadat Ali Khan v. Mirza Wiquar Ali Beg and others (AIR 1943 PC 115), Chandu Lal Aarwalla and another v. Khalilur Rahaman and others (AIR 1950 PC 17), Shashibhushan Prasad Mishra and another v. B Babuji Rai and others (AIR 1970 SC 809), Iftikhar Ahmed and others v. Syed Meharban Ali and others (AIR 1974 SC 749) and Janardhanan Pillai v. Kochunarayani Amma (1976 KLT 279), considered the question of res judicata between codefendants. The rule of res judicata while founded on ancient precedent is dictated by a wisdom for all time and the application of the rule should be influenced by no technical considerations of form, but by matter of substance within the limits allowed by law. The raison de'tre (reason or purpose) of the rule is to confer finality on decisions arrived at by competent courts between interested parties after genuine contest. It corresponds to what is known as estoppel by judgment in English law. It is based partly on the rule of public policy that it concerns the State that there be an end of law suits and partly on private justice that no man should be vexed twice over for the same cause. S.11 of the Code of Civil Procedure grants a prohibitory injunction against courts not to try a suit or issue in which the matter was directly and substantially in issue between the parties or under whom they cl