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Economic, Commercial and Intellectual Property Laws · Intellectual Property Rights

Rights of Patentee, Co-owners and Dealing with Patents

Updated 11 October 2026 · Fact-checked

Where a patent is granted to two or more persons, section 50 of the Patents Act, 1970 gives each an equal undivided share unless agreed otherwise. Each may use the invention for his own benefit without accounting, but needs the others' consent to license or assign. Section 70 lets registered owners deal with the patent.

Understand Rights of Patentee, Co-owners and Dealing with Patents

A patent gives its owner the rights in section 48. Section 50(2) refers to these as "the rights conferred by section 48". The owner can use the invention and stop others from doing so. The owner can also deal with the patent: assign it, license it, or give it as security.

A patent can be granted to more than one person. These persons are co-owners. Section 50 sets default rules for them. Every default can be changed by an agreement between the co-owners. So always read the facts for an agreement first.

There are three default rules. First, shares are equal and undivided (section 50(1)). Second, each co-owner may exploit the patent himself or through agents for his own benefit, without accounting to the others (section 50(2)). Third, no co-owner can grant a licence or assign his share without the consent of the others (section 50(3)).

Two more points matter. If one co-owner sells a patented article, the buyer and those claiming through him can deal with it as if a sole patentee had sold it (section 50(4)). Apart from this, the general rules of law on ownership and devolution of movable property apply to patents (section 50(5)).

Section 51 handles deadlock. A registered co-owner can apply to the Controller, who may give directions on sale or lease of the patent, grant of licences, or exercise of section 50 rights. Section 70 is the general power: registered grantees or proprietors can assign, license or otherwise deal with the patent and give effectual receipts, subject to the co-ownership provisions and to rights noted in the register.

Key rules to remember

Share of co-owners (s 50(1))
Patent granted to 2 or more persons → equal undivided shares, unless agreement to the contrary
The agreement can change the shares. Without one, shares are equal.
Working the patent (s 50(2))
Each registered co-owner may exercise section 48 rights for own benefit, without accounting to the others
Subject to sections 50 and 51, and unless agreement to the contrary is in force.
Licence or assignment (s 50(3))
No licence and no assignment of a share without the consent of the other co-owners
Subject to sections 50, 51 and any agreement in force.
Sale of patented article (s 50(4))
Buyer and those claiming through him deal with the article as if sold by a sole patentee
Protects buyers from claims by other co-owners.
Controller's directions (s 51)
Application by a registered co-owner → hearing to others → directions on sale, lease, licences or s 50 rights
If a person fails to act within fourteen days of written request, the Controller may authorise another to sign for him. No direction may affect trustees' or legal representatives' mutual rights, or be inconsistent with an agreement.
Power to deal (s 70)
Registered grantee or proprietor may assign, license or deal with the patent and give effectual receipts
Subject to co-ownership provisions and rights noted in the register. Equities can be enforced as for other movable property.

How to solve Rights of Patentee, Co-owners and Dealing with Patents questions

Use this method for any question on rights of co-owners or dealing with a patent.

  1. 1Identify who is registered as grantee or proprietor. Is it one person or two or more?
  2. 2Check for an agreement between them. Section 50 defaults apply only where no contrary agreement is in force.
  3. 3Name the act in question: using the invention, licensing, assigning a share, or selling a patented article.
  4. 4Apply the matching sub-section: s 50(2) for own use, s 50(3) for licence or assignment, s 50(4) for sale of articles.
  5. 5If there is a dispute or deadlock, bring in section 51 and the Controller's directions, with the right to be heard.
  6. 6Add section 70 for the general power to assign or license, subject to co-ownership and register entries.
  7. 7Write a clear conclusion that answers the exact question asked.

Quickest way: Three-question check

When to use it: Use for short problem questions with limited time.

  1. Is there an agreement? If yes, it governs.
  2. Is the act personal use, or licence/assignment? Personal use needs no consent and no accounting. Licence or assignment needs consent.
  3. Is there a deadlock? Mention section 51 and the Controller.

Common mistakes in Rights of Patentee, Co-owners and Dealing with Patents

  • Saying a co-owner must share profits from his own working of the patent.

    Students apply partnership or property logic.

    Fix: Section 50(2) says each may exercise the rights for his own benefit without accounting, unless an agreement says otherwise.

  • Saying a co-owner can license freely because he owns a share.

    Students mix up personal use with dealing.

    Fix: Under section 50(3), licence or assignment of a share needs the consent of the other co-owners.

  • Ignoring the agreement clause.

    Students memorise the defaults only.

    Fix: Begin every answer by checking for a contrary agreement. It overrides the defaults.

  • Treating section 70 as an unrestricted power.

    Students read only the first part of the section.

    Fix: Section 70 is subject to the co-ownership provisions and to rights noted in the register.

  • Forgetting the Controller's role in a deadlock.

    Students think section 50 is the whole topic.

    Fix: Cite section 51: application, hearing for the other persons, directions, and the fourteen-day default rule.

Worked examples

Example 1

Ravi and Sunita are registered joint grantees of a patent. They have no agreement. Ravi manufactures the patented product in his own factory and keeps all profits. Sunita demands half the profits. Advise.

Show the solution
  1. Two persons are registered as grantees, so section 50 applies.
  2. No agreement is in force, so the defaults operate. Each has an equal undivided share (s 50(1)).
  3. Under section 50(2), each may exercise section 48 rights himself or through agents, for his own benefit, without accounting to the other.
  4. So Ravi's working of the patent in his own factory needs no consent from Sunita, and he need not share the profits.

Answer: Sunita cannot claim half the profits. Ravi may work the patent for his own benefit without accounting, as there is no contrary agreement. They may agree otherwise in future.

Example 2

Anil and Bhavna hold a patent jointly with no agreement. Anil grants a licence to Zenith Ltd. without telling Bhavna. Bhavna refuses consent. Can Anil's licence stand, and what can Anil do?

Show the solution
  1. Section 50(3) bars the grant of a licence by one co-owner except with the consent of the other.
  2. Bhavna has not consented, so Anil's licence does not comply with section 50(3).
  3. Anil may apply to the Controller under section 51(1) for directions on the grant of licences under the patent.
  4. The Controller must first give Bhavna an opportunity to be heard (s 51(3)(a)).
  5. The Controller may give directions as he thinks fit, but cannot give any inconsistent with an agreement between the co-owners (s 51(4)).

Answer: Anil's licence is not valid without Bhavna's consent. His remedy is to apply to the Controller under section 51, who will hear Bhavna before giving directions.

Exam tips

  • State section 50 defaults and always add the words 'unless an agreement to the contrary is in force'.
  • Use the exact verbs: licence and assignment need consent; personal use does not.
  • Cite sections 50, 51 and 70 together in problem answers. Examiners reward the link.
  • Structure answers as provision, application, conclusion.
  • Remember the fourteen-day period and the right to be heard in section 51.

Practice questions from Intellectual Property Rights

Rights of Patentee, Co-owners and Dealing with Patents in other exams

The same ground in other exams, if you are preparing for more than one or want another angle on it.

Rights of Patentee, Co-owners and Dealing with Patents: frequently asked questions

What does section 50 of the Patents Act say?

It sets default rules for co-owners. Shares are equal and undivided, each may use the invention for his own benefit without accounting, and licence or assignment needs the others' consent. An agreement can change all of these.

Can one co-owner sell the patented article?

Yes. Under section 50(4), the buyer and those claiming through him may deal with the article as if it were sold by a sole patentee.

What is the power under section 70?

Registered grantees or proprietors can assign, license or otherwise deal with the patent and give effectual receipts. This is subject to co-ownership provisions and rights noted in the register.

What happens if co-owners cannot agree?

A registered co-owner may apply to the Controller under section 51. The Controller hears the other persons and then gives directions on sale, lease, licences or exercise of section 50 rights.