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Intellectual Property Rights - Law and Practice · Indian Patent Law and its Developments

Patentable Subject Matter and Conditions under the Patents Act

Updated 11 October 2026 · Fact-checked

A patentable invention under the Patents Act, 1970 is a new product or process that involves an inventive step and is capable of industrial application (Section 2(1)(j)). It must also avoid the exclusions in Sections 3 and 4. To solve a question, test the three conditions, then check the exclusions.

Understand Patentable Subject Matter and Conditions

A patent protects an invention. The Act does not protect every clever idea. It defines an invention in Section 2(1)(j) as a new product or process involving an inventive step and capable of industrial application. Everything in this topic grows from that one definition.

There are three positive tests. Novelty means the invention has not been anticipated by publication in any document, or used in India or elsewhere in the world, before the date of filing with complete specification (Section 2(1)(l)). It must not form part of the state of the art. Inventive step means a feature that involves technical advance over existing knowledge, or has economic significance, or both, and makes the invention not obvious to a person skilled in the art (Section 2(1)(ja)). Capable of industrial application means the invention can be made or used in an industry (Section 2(1)(ac)).

Then comes the negative test. Even if the three conditions are met, the subject matter must not fall under Section 3 (what are not inventions) or Section 4 (atomic energy). Section 3 covers frivolous inventions, inventions contrary to public order or morality, mere discovery, mere new forms of known substances, mere admixtures, mere arrangement of known devices, agricultural methods, medical treatment methods, plants and animals, business methods and computer programmes per se, aesthetic creations, presentation of information, topography of integrated circuits, and traditional knowledge.

Many exclusions use words like mere and per se. These words matter. A discovery is excluded, but an invention that applies a discovery in a new way may not be. A computer programme per se is excluded, but this does not say that every invention using software is excluded. Always read the exact wording.

Note also that Section 5, which once limited some fields to process patents, has been omitted with effect from 1 January 2005. Product patents are now possible in all fields, subject to Sections 3 and 4.

Key rules to remember

Invention (Section 2(1)(j))
Invention = new product or process + inventive step + capable of industrial application
All three elements must be present. Missing any one means no patentable invention.
Novelty (Section 2(1)(l))
Not anticipated by publication in any document or use in India or elsewhere before the filing date with complete specification
The subject matter must not be part of the state of the art or in the public domain.
Inventive step (Section 2(1)(ja))
Technical advance over existing knowledge, or economic significance, or both + not obvious to a person skilled in the art
Both limbs matter: the advance and the non-obviousness.
Industrial application (Section 2(1)(ac))
Capable of being made or used in an industry
The test is capability, not actual commercial use.
Section 3(d) explanation
Salts, esters, ethers, polymorphs, metabolites, pure form, particle size, isomers, mixtures of isomers, complexes, combinations and other derivatives of a known substance = same substance, unless they differ significantly in properties with regard to efficacy
A new form of a known substance needs enhanced known efficacy to qualify.
Section 4
No patent for an invention relating to atomic energy falling within Section 20(1) of the Atomic Energy Act, 1962
An absolute bar, separate from Section 3.

How to solve Patentable Subject Matter and Conditions questions

Use this order for any problem or theory question on patentability. It mirrors how a Patent Office examiner would think, and it gives you a clear provision, analysis and conclusion structure.

  1. 1Identify what is claimed. State in one line whether it is a product, a process, or something else such as a method or a scheme.
  2. 2Check Section 2(1)(j). Ask if it is a new product or process, with an inventive step, and capable of industrial application.
  3. 3Test novelty using Section 2(1)(l). Look in the facts for prior publication or prior use, in India or anywhere in the world, before the filing date.
  4. 4Test inventive step using Section 2(1)(ja). Ask if a person skilled in the art would find it obvious, and whether there is technical advance or economic significance.
  5. 5Test industrial application using Section 2(1)(ac). Ask if it can be made or used in an industry.
  6. 6Run through the Section 3 clauses and Section 4. Match the facts to the clause wording, especially words like mere, per se and known substance.
  7. 7Apply the law to the facts and discuss both sides where the facts are close.
  8. 8Write a clear conclusion: patentable, not patentable, or patentable only if certain conditions are met.

Quickest way: Three tests plus one filter

When to use it: Use this when you have little time, for a short-note or a quick case question.

  1. Write the Section 2(1)(j) definition in one line.
  2. Tick novelty, inventive step and industrial application one by one against the facts.
  3. Scan Section 3 and 4 for the clause that fits. Name the clause letter only if you are sure of it.
  4. Give a one-line conclusion with the reason.

Common mistakes in Patentable Subject Matter and Conditions

  • Treating any new idea as a patentable invention.

    Students focus only on novelty and ignore inventive step and industrial application.

    Fix: Always apply all three tests of Section 2(1)(j). Novelty alone is not enough.

  • Saying all software is unpatentable.

    Section 3(k) is remembered without its qualifier.

    Fix: Quote the exact words: a mathematical or business method or a computer programme per se or algorithms. Discuss whether the claim is only the programme itself.

  • Treating a new form of a known drug as automatically patentable.

    Students overlook the Section 3(d) explanation.

    Fix: Say that salts, polymorphs, isomers and similar forms are the same substance unless they differ significantly in properties with regard to efficacy.

  • Limiting novelty to prior use or publication in India.

    Students assume patent law is purely territorial.

    Fix: Section 2(1)(l) covers publication in any document, and use in the country or elsewhere in the world, before the filing date.

  • Mixing up Section 3 and Section 4.

    Both deal with non-patentable matter.

    Fix: Section 3 lists what are not inventions. Section 4 is a separate bar on inventions relating to atomic energy.

  • Citing Section 3(g) or Section 5 as current law.

    Older notes still mention them.

    Fix: Clause (g) of Section 3 has been omitted, and Section 5 has been omitted from 1 January 2005. Mention them only to contrast with the earlier law.

Worked examples

Example 1

Anil Rao, a researcher in Pune, finds a naturally occurring bacterium in soil and files a claim on the bacterium as found. Another claim covers a new industrial process of using a known mixture of salts to treat effluent. Advise on patentability of the first claim.

Show the solution
  1. Provision: Section 3(c) says the mere discovery of a scientific principle, or discovery of any living thing or non-living substance occurring in nature, is not an invention.
  2. Facts: The bacterium occurs in nature and Anil has only found it. He has not created or modified it.
  3. Analysis: The claim is a mere discovery of a living thing occurring in nature. The definition of invention requires a new product or process, and a found organism is not a product of human invention here.
  4. Contrast: If he had developed a genetically engineered or otherwise new strain through his own technical work, the position would need fresh analysis against Section 2(1)(j) and Section 3(j), which excludes plants and animals but not micro-organisms.
  5. Conclusion: The first claim as framed is not patentable.

Answer: The claim on the naturally occurring bacterium is not patentable because it is a mere discovery of a living thing occurring in nature under Section 3(c).

Example 2

Meera Pharma Ltd. has a known drug that treats hypertension. It files for a patent on a new crystalline polymorph of the same drug. Tests show the polymorph is more stable on the shelf but has the same therapeutic efficacy. Examine whether the polymorph is patentable.

Show the solution
  1. Provision: Section 3(d) excludes the mere discovery of a new form of a known substance which does not result in enhancement of the known efficacy of that substance.
  2. Explanation: The Explanation treats polymorphs and other listed forms as the same substance, unless they differ significantly in properties with regard to efficacy.
  3. Facts: The polymorph is a new form of a known substance. The improvement is shelf stability. Therapeutic efficacy is unchanged.
  4. Analysis: The test in Section 3(d) is enhancement of known efficacy. Better stability does not show that efficacy has been enhanced, so the polymorph is treated as the same substance.
  5. Check other tests: Even if there were novelty, the claim fails at the Section 3(d) filter.
  6. Conclusion: The polymorph is not patentable on these facts.

Answer: The polymorph is not patentable under Section 3(d) because it is a new form of a known substance with no enhancement of known efficacy, and the improved stability does not meet the test.

Exam tips

  • Begin every answer with the Section 2(1)(j) definition and then the three tests. Examiners look for this structure first.
  • Quote key phrases such as per se, mere discovery and known efficacy. Marks follow the exact wording of the Act.
  • In case-based questions, discuss the facts against each clause and give a clear conclusion. Do not just list Section 3.
  • Mention the omitted provisions (Section 3(g) and Section 5) only when contrasting with the earlier law.
  • As the elective is open book, mark the Section 2(1) definitions and the Section 3 clauses in your copy for fast reference, but still practise writing the reasoning.

Practice questions from Indian Patent Law and its Developments

Patentable Subject Matter and Conditions in other exams

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

Patentable Subject Matter and Conditions: frequently asked questions

What is a patentable invention under the Patents Act, 1970?

It is a new product or process that involves an inventive step and is capable of industrial application, as defined in Section 2(1)(j). It must also not fall under Section 3 or Section 4. All conditions must be met together.

What is the difference between Section 3 and Section 4?

Section 3 lists matters that are not inventions, such as mere discoveries, business methods and computer programmes per se. Section 4 bars patents for inventions relating to atomic energy falling within Section 20(1) of the Atomic Energy Act, 1962.

How is inventive step defined in the Act?

Section 2(1)(ja) defines it as a feature of an invention that involves technical advance over existing knowledge, or has economic significance, or both, and makes the invention not obvious to a person skilled in the art.

Are computer programmes patentable in India?

Section 3(k) excludes a mathematical or business method or a computer programme per se or algorithms. The words per se are important. A claim must be examined on its facts to see whether it is only the programme or something more.

Can a new form of a known substance be patented?

Only if it differs significantly in properties with regard to efficacy. Section 3(d) and its Explanation treat salts, polymorphs, isomers and similar forms as the same substance unless they show enhanced known efficacy.