Short Note : Facts, in brief, leading to the present revision are that the non-applicant No. 1-plaintiff instituted a suit against the applicant defendant under section 27 of the Trade and Merchandise Marks Act, 1958 for infringement of its trade mark by the registered partnership firm consisting of several partners including one Kodumal son of Khemchand, who is now shown here as non applicant No.2. The case of the plaintiff was that it was a registered proprietor of the trade mark "RR" and it was carrying on the business of manufacturing soap with the said trade mark. According to the applicant defendant, the plaintiff firm was not the registered trade mark proprietor. Subsequently, an application under O.1, R.10 along with an application under O.6., R.17 of the Code was moved on behalf of the plaintiff in which the non-applicant No.2 was also joined, pleading that non-applicant No.2 be added as plaintiff No.2 in the array of plaintiffs. The amendment of the plaint was sought for adding that the trade mark "RR" has been registered in the name of "Kodumal Khemchand, Karta of the joint Hindu family concern which is trading in the name of Ranjeet Soap Factory" but in the cause title the name of the registered partnership firm has alone been mentioned. According to the application for amendment Kodumal Khemchand is the partner of the plaintiff firm, which is a registered one and, therefore, joining of non-applicant No.2 in the array of plaint and consequential amendment in the plaint would be in the interest of justice as there is no difference between the joint Hindu family of which Kodumal Khemchand is the Karta and the plaintiff partnership concern. Thus, it was tried to be pleaded that addition of non-applicant No.2 as an additional plaintiff would meet the ends of justice in the case. On the other hand the application was opposed by the contesting defendant on the ground that the application under Order 1, rule 10 of the Code for joining non-applicant No. 2 as plaintiff No.2 is wholly innocuous as the said non-applicant is already a partner in the plaintiff concern and, therefore, the provisions of Order 1, rule 10 of the Code would not be attracted for a person who is already a party to the suit. It was also pleaded that the registered firm and the joint Hindu family of which Kodumal Khemchand has been alleged as the Karta are two different entities and, therefore, if the joinder is permitted it would be setting up a new case and also on a different cause of action, which cannot be permitted. The trial Court allowed the application under Order 1, rule 10 as also the other application under Order 6, rule 17 of the Code. Hence this revision by the applicant-defendant. Held : No doubt, the question of addition of parties under Order 1, rule 10 of the Code is generally not one of initial jurisdiction of the Court but of a judicial jurisdiction which has to be exercised in view of all the facts and circumstances of the case. In case, where the order amounts to failure to exercise jurisdiction or that jurisdiction has been exercised with illegality or with material irregularity in directing a party to be improperly added, causing a misjoinder of parties or the order is manifestly unjust, the Court would certainly be competent to interfere under section 115 of the Code. Therefore, in the present case if it can be found that the impugned order suffers with that infirmity, then certainly it would be liable to be interfered with otherwise not. In the present case, it was not disputed before me that the suit has been filed by a registered firm. Now by virtue of the impugned order non-applicant No. 2 has been ordered to be joined as plaintiff No.2 on the ground that there is a joint Hindu family concern in the name of Kodumal Khemchand of which Kodumal is the Karta. By the impugned order on the basis of camouflage of mis-description of the plaintiff what has been done is that a joint Hindu family concern has been impleaded as a party in the array of plaintiff or to say in other words Kodumal, who is alleged to be the Karta, has been sought to be added as an additional plaintiff. The effect of the amendment is that there would be now two plaintiffs whose identity differs from each other. It cannot be denied that a joint Hindu family firm is quite a different legal entity from the firm registered under the Indian Partnership Act. The effect of the amendment is that there would be now two plaintiffs whose identity differs from each other. It cannot be denied that a joint Hindu family firm is quite a different legal entity from the firm registered under the Indian Partnership Act. Once a joint partnership is created by operation of law, a partnership under the Indian Partnership Act is one arising out of a contract. In case of a mis-description there is only an alternation in the name of the plaintiff, the legal entity of the person or body suing remains the same. While in the case of substitution of one plaintiff for another, there is change in the legal person or entity suing. In the present case, it was a misnomer what is called to be under Order 1, rule 10 of the Code on the basis of a mis-description as has been held by the trial Court. The Court will not grant leave to add a party where the result will be to introduce a cause of action with which the plaintiff has nothing to do. What is now sought to be incorporated by the application under Order 1, rule 10 or Order 6, rule 17 of the Code is to convert the present suit as one of the Hindu joint family concern having a registered trade mark "R" to one on behalf of the present plaintiff. That being so, by joining Kodumal (non-applicant No.2) as a plaintiff, his joinder would entail in misjoinder of plaintiffs and causes of action. The reason is obvious. As stated earlier the joinder of non-applicant No. 2 was sought in the capacity which was different from his capacity as partner in the firm, then by joining him, the cause of action would be distinct and different, in which case no amendment could be permitted. Not only that but the amendment if allowed to stand it would involve in setting up a new case and altering the real matter in controversy between the parties, which cannot be allowed AIR 1950 PC 68 relied on. Revision allowed.