The basic doctrine of trademark is ‘one mark, one source and one proprietor’. The single proprietor of a trademark may either be an individual or a jointly owned single entity i.e., Partnership firm, Limited Liability Partnership firm (LLP) or a Company established as per the laws of India or others i.e., trust, Non-governmental Organization etc. The logic behind one mark, one source and one proprietor is to avoid confusion and deception amongst the public. However, Section 24 of The Trademarks Act, 1999 shows a slight shift from the normal paradigm of one mark one source and allows the trademark to be owned by multiple owners. The joint ownership of Trademark is completely valid as per the laws of India.
According to section 24 of The TradeMarks Act, 1999, two or more persons (be it an individual/companies/firms/LLP/entities etc) can make an application jointly for registration of same mark as a ‘Joint Proprietors’ or ‘Joint Owners’ of the mark. The trademark shall be registered in favour of those entities/parties jointly.
Once the trademark is registered in the joint names, by operation of law, the right to use the trademark is equally vested in all the registered owners. Section 24 lays down the rules for Jointly owned trademark. All intellectual property attached to and associated with the registered mark are vested to all the joint owners of the mark. The ownership of the parties in respect of the trademark is joint together as single person and is indivisible. No single person of the joint owners can have a exclusive control over the mark or its use.
All revenues from the business carried on by using the trademark shall be shared and distributed to the joint owners in equal proportion. All the Joint owners shall have equal rights and the goodwill created after the joint use of the mark by Joint Owners shall vest in and shared by the parties jointly as if they are a single person, and neither party shall have a claim or control over such goodwill.
Most importantly, the joint proprietors cannot use the mark independently or unilaterally against the interest of each other in any manner whatsoever, either directly or indirectly. The court has held that ‘the joint proprietors must use the trademark jointly for the benefit of all. It cannot be used in rivalry and in competition with each other’. 
The biggest disadvantage of filing an application as Joint owners is that even if one of the Joint owners decides to split, then the rights of all the joint owners will be dissolved. No one can claim any ownership over the mark individually. However, all the joint owners can give prior permission to one of the owners for using the mark by way of licensing or assigning.
Further, neither of the joint owner/proprietor shall be entitled to assign or otherwise transfer his/her right, title and interest in and upon the mark to any third party without the consent of other co-owners. The Joint owners can mutually assign or transfer the marks to the third party.
Procedure for Registration of a Trademark to be owned Jointly:
An application for registration of the mark by the Joint owners can be made by filing the form TMA. The documents required are similar to what is required for filing of a mark by a single Applicant. The only additional step for filing application as Joint Proprietor, is to add the details of each of the proprietors and select the Category as ‘Joint Applicant’. The fees for filing trademark application in case of Joint Applicants, irrespective of the number of Joint Applicants will be 9000 INR only.
Either of the parties of the joint ownership must have a place for their business within the territory of India and it would be mandatory for them to have their address for service in India as laid down in Section 18(3) of The Trademarks Act,1999.
The application by the Joint proprietors can be made for the mark which is already in use by the Joint owners, or they may propose to use it.
Since the application for joint proprietors in considered as single application, the remaining rules of application, oppositions, registration, renewals will be the same as applicable to application owned by a single entity.
Although no proof of relevant agreements specifying the joint Venture is required, the Trademarks Registry may call upon the Applicants to produce the supporting Joint venture Agreements.
 Section 24 The Trademarks Act, 1999:
Jointly owned trademarks. —
(1) Save as provided in sub-section (2), nothing in this Act shall authorise the registration of two or more persons who use a trademark independently, or propose so to use it, as joint proprietors thereof.
(2) Where the relations between two or more persons interested in a trademark are such that no one of them is entitled as between himself and the other or others of them to use it except—
(a) on behalf of both or all of them; or
(b) in relation to an article or service with which both or all of them are connected in the course of trade, those persons may be registered as joint proprietors of the trademark, and this Act shall have effect in relation to any rights to the use of the trademark vested in those persons as if those rights had been vested in a single person.
 1994 SCR (1) 708, 1994 SCC (2) 448, Power Control Appliances vs Sumeet Machines Pvt. Ltd.
 Section 18 in The Trade Marks Act, 1999
18. Application for registration. — (1) Any person claiming to be the proprietor of a trade mark used or proposed to be used by him, who is desirous of registering it, shall apply in writing to the Registrar in the prescribed manner for the registration of his trade mark.
(2) A single application may be made for registration of a trade mark for different classes of goods and services and fee payable therefor shall be in respect of each such class of goods or services.
(3) Every application under sub-section (1) shall be filed in the office of the Trade Marks Registry within whose territorial limits the principal place of business in India of the applicant or in the case of joint applicants the principal place of business in India of the applicant whose name is first mentioned in the application as having a place of business in India, is situate: Provided that where the applicant or any of the joint applicants does not carry on business in India, the application shall be filed in the office of the Trade Marks Registry within whose territorial limits the place mentioned in the address for service in India as disclosed in the application, is situate.