An invention is patentable if it satisfies three positive requirements (novelty, inventive step, industrial application) AND does not fall within any of the exclusions under S.3 or S.4. Section 3 lists 15 categories of subject matter (S.3(a)-(h) and S.3(j)-(p); S.3(i) was deleted by the 2002 Amendment) that are "not inventions" regardless of novelty or utility. Section 4 bars inventions relating to atomic energy.
Why: Exclusions reflect India's policy choices: keeping nature, abstract ideas, traditional knowledge, and methods of treatment outside the patent system to preserve access to basic knowledge, healthcare, food security, and biodiversity.
Legal Framework
Positive requirements
| Requirement | Section | Standard |
|---|---|---|
| Novelty | S.2(1)(l) | Not anticipated by publication or use anywhere in world before priority date |
| Inventive step | S.2(1)(ja) | Technical advance over existing knowledge OR economic significance; non-obvious to person skilled in art |
| Industrial application | S.2(1)(ac) | Capable of being made or used in industry, including agriculture |
Anticipation (destroying novelty)
| Type of prior art | Section | Rule |
|---|---|---|
| Prior publication | S.29 | Published in any document in any country before priority date |
| Prior claiming | S.30 | Claimed in a specification filed before priority date (even if unpublished at that time) |
| Prior knowledge | S.31 | Publicly known or used in India before priority date |
| Prior use | S.32 | Used in India before priority date |
| Disclosure at exhibition | S.31(e)-(f) | Publication at industrial exhibition within 12 months before filing does NOT destroy novelty (grace period) |
Non-Patentable Subject Matter (S.3)
| Sub-section | Exclusion | Example |
|---|---|---|
| S.3(a) | Frivolous; contrary to natural laws | Perpetual motion machine |
| S.3(b) | Contrary to public order/morality; prejudicial to life/health/environment | Biological weapon; gambling device |
| S.3(c) | Mere discovery of scientific principle or abstract theory | E = mc²; law of gravity |
| S.3(d) | New form of known substance without enhanced efficacy | Polymorphs, salts, esters of known drugs (unless efficacy is significantly enhanced) |
| S.3(e) | Mere admixture/aggregation of properties | Mixing two known chemicals without synergistic effect |
| S.3(f) | Mere arrangement/duplication of known devices | Combining known components functioning independently |
| S.3(g) | Method of agriculture or horticulture | Crop rotation method; pruning technique |
| S.3(h) | Method of treatment (medical/surgical/curative/diagnostic) of humans/animals | Surgical technique; diagnostic method |
| S.3(j) | Plants and animals in whole or any part thereof other than micro-organisms; seeds, varieties, species; essentially biological processes for production/propagation of plants and animals | Natural breeds; conventional cross-breeding; genetically selected plant variety |
| S.3(k) | Mathematical methods; business methods; computer programmes per se; algorithms | Pure algorithm; mobile app business model |
| S.3(l) | Literary, dramatic, musical, artistic work (aesthetic creation) | Novel, painting, musical composition |
| S.3(m) | Scheme/rule/method of performing mental act or playing game | Chess strategy; meditation technique |
| S.3(n) | Presentation of information | Particular layout of printed matter |
| S.3(o) | Topography of integrated circuits | Protected under SICLD Act separately |
| S.3(p) | Traditional knowledge or aggregation/duplication of known properties of traditionally known components | Turmeric for wound healing (documented TK) |
S.3(d) in detail (most examined provision)
"the mere discovery of a new form of a known substance which does not result in the enhancement of the known efficacy of that substance"
Explanation to S.3(d): salts, esters, ethers, polymorphs, metabolites, pure form, particle size, isomers, mixtures of isomers, complexes, combinations, and other derivatives of known substance shall be considered the same substance UNLESS they differ significantly in properties with regard to efficacy.
Why: S.3(d) targets "evergreening" strategies where pharmaceutical companies seek new patents on trivial modifications (changing salt form, crystalline structure) of existing drugs to extend monopoly beyond 20 years. India demands proof of "significantly enhanced efficacy" (therapeutic efficacy for drugs, per Novartis).
S.4: Atomic energy inventions
Inventions relating to atomic energy within the meaning of the Atomic Energy Act, 1962 are not patentable.
Illustrations: S.3(d) in Practice
Example 1 — Fails S.3(d) (like Novartis): Drug X exists as a free base form (patent expired). PharmaCo files for the hydrochloride salt form claiming: "better shelf-life (36 vs 24 months), improved dissolution, easier to formulate into tablets." But clinical data shows SAME blood pressure reduction in patients. Result: S.3(d) bars the patent. Improved physical properties (shelf-life, dissolution) ≠ enhanced therapeutic efficacy.
Example 2 — Passes S.3(d): Drug Y exists as a racemic mixture (50:50 of R and S enantiomers). PharmaCo isolates the S-enantiomer and shows: (a) 3x lower dosage needed, (b) 70% reduction in side effects (liver toxicity), (c) clinical trials demonstrate superior patient outcomes. The S-enantiomer shows significantly enhanced therapeutic efficacy (not just better physical properties). Patent likely granted.
Example 3 — The "per se" trap in S.3(k): Company A files patent for "an algorithm that sorts data alphabetically." Refused: computer programme per se (S.3(k)). Company B files for "a method of reducing fuel injection timing error in diesel engines using a feedback algorithm executed on an ECU." This may succeed: the software produces a technical effect (improved engine performance) as part of a larger hardware system. It's not software "per se."
Example 4 — S.3(h) boundary: A surgeon invents a new laparoscopic technique for gallbladder removal requiring 60% less incision. The METHOD (how to cut, where to insert, angle of instrument) is unpatentable under S.3(h). But: a new surgical INSTRUMENT designed for this technique (a specially shaped trocar) IS patentable — it's a product, not a method of treatment.
Recall Check
- List five exclusions under S.3 that are unique to Indian patent law (not found in most other jurisdictions).
- What does "enhanced efficacy" mean in the context of S.3(d) for pharmaceutical inventions?
- What is the difference between S.3(c) (discovery of scientific principle) and a patentable invention based on that principle?
Key Cases
Novartis AG v. Union of India (2013) Novartis-AG-v-Union-of-India-2013 Issue: Whether the beta-crystalline form of imatinib mesylate (Glivec) was a new form of a known substance showing enhanced efficacy under S.3(d). Rule: "Efficacy" in S.3(d) for pharmaceutical substances means "therapeutic efficacy"; a new form must show significantly enhanced therapeutic efficacy over the known substance, not merely improved physical properties (bioavailability, stability, flow properties). Held: Patent refused. Novartis failed to demonstrate significantly enhanced therapeutic efficacy of the beta-crystalline form over the known free base. Improved bioavailability alone is insufficient. S.3(d) is constitutionally valid and TRIPS-compliant.
Biswanath Prasad v. Hindustan Metal Industries (1979) Biswanath-Prasad-v-Hindustan-Metal-Industries-1979 Issue: Whether a workshop improvement in brass pot manufacturing involved an inventive step. Rule: "Inventive step" requires that the advance not be obvious to a person skilled in the art; a mere workshop improvement or trade variation without technical advance is not patentable. Held: Patent revoked for lack of inventive step. The alleged invention would be obvious to any skilled artisan in the trade; no technical advance was demonstrated.
F. Hoffmann-La Roche v. Cipla (2008) Hoffmann-La-Roche-v-Cipla-2008 Issue: Whether interim injunction should be granted to prevent Cipla from selling generic erlotinib (cancer drug) pending patent infringement trial. Rule: In pharmaceutical patent cases, public interest in access to life-saving drugs may outweigh the patentee's right to interim injunction; damages may be adequate remedy. Held: Interim injunction refused. Public interest in affordable cancer treatment outweighed Roche's interest; damages could adequately compensate if infringement is later established. Balance of convenience favoured public access.
Distinctions
| Parameter | Patentable Invention | Non-Patentable (S.3) |
|---|---|---|
| Discovery vs invention | Invention (human-made, technical application) | Discovery (finding what exists in nature: S.3(c)) |
| New form with efficacy | New polymorph showing 5x better absorption + therapeutic outcome | New polymorph with same therapeutic effect but better stability (S.3(d)) |
| Software | Software controlling hardware to produce technical effect | Algorithm/computer programme per se (S.3(k)) |
| Biological | Genetically modified micro-organism (Diamond v. Chakrabarty) | Plant variety, seed, essentially biological process (S.3(j)) |
| Treatment | Drug compound for treating disease (product patent) | Method of surgery/diagnosis on human body (S.3(h)) |
Flashcards
Q: How many categories of non-patentable subject matter does S.3 list? A: 15 active categories (S.3(a) through S.3(h) and S.3(j) through S.3(p); S.3(i) was deleted by the 2002 Amendment).
Q: What is the "enhanced efficacy" requirement under S.3(d)? A: A new form of known substance must show significantly enhanced efficacy (therapeutic efficacy for drugs) to be patentable; improved physical properties alone are insufficient.
Q: What did Novartis v. Union of India (2013) establish? A: "Efficacy" in S.3(d) means therapeutic efficacy for pharmaceutical substances; improved bioavailability without enhanced therapeutic outcome does not satisfy S.3(d).
Q: Are methods of medical treatment patentable in India? A: No. S.3(h) excludes methods of medical, surgical, curative, prophylactic, diagnostic, or therapeutic treatment of humans or animals.
Q: Can computer programs be patented in India? A: Computer programmes "per se" are excluded (S.3(k)), but software producing a technical effect as part of a larger invention (e.g., improved hardware control) may be patentable.
Q: What does S.3(p) exclude? A: Inventions which are traditional knowledge or aggregation/duplication of known properties of traditionally known components.
Q: What is the "person skilled in the art" test for inventive step? A: The notional skilled person has ordinary knowledge and skill in the relevant field; if the invention would be obvious to this person, it lacks inventive step and is not patentable.
Q: What is the difference between a discovery (S.3(c)) and a patentable invention? A: A discovery merely finds what exists in nature (gravity, DNA structure); an invention applies a discovery to create something new and useful (a device using gravitational principles, a recombinant DNA technique).
Exam Scenario
PharmaCo holds a patent for Drug X (a known anti-hypertensive). It now files a patent application for the sodium salt form of Drug X, claiming improved shelf-life (36 months vs. 24 months) and better dissolution rate, but with the same therapeutic effect on blood pressure.
Advise: (a) Whether the sodium salt form is a "new form of a known substance" under S.3(d). (b) Whether improved shelf-life and dissolution rate constitute "enhanced efficacy" per Novartis v. Union of India. (c) What evidence PharmaCo would need to demonstrate to overcome the S.3(d) bar. (d) Whether a pre-grant opposition under S.25(1) could be filed on this ground by a generic manufacturer.
See Also
- IoS-2.3 Mischief Rule — S.3(d) exclusions interpreted using Heydon's rule: the mischief was "evergreening" (extending patent monopoly through trivial modifications); Novartis v. Union of India explicitly applies mischief rule to S.3(d)
- IoS-3.1 Penal Statutes — patent exclusions under S.3 are strictly construed; any ambiguity in what constitutes an excluded subject matter resolved in favour of the applicant (penal/restrictive provisions construed narrowly)
- TRIPS Agreement 1994 and Its Impact — TRIPS Art. 27.1 requires patentability in all fields of technology; S.3(d) challenged as TRIPS-inconsistent; Doha Declaration on public health provides flexibilities