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Delhi High Court revisits test for inventive step - International Law Office

International Law Office

Intellectual Property - India

Delhi High Court revisits test for inventive step

September 13 2010


In Asian Electronics Ltd v Havells India Limited(1) the Delhi High Court looked into the basic criteria of patentability, particularly with regard to non-obviousness or inventive step.


The three criteria for the grant of a patent are:

  • non-obviousness;
  • novelty; and
  • industrial application.

'Non-obvious' as a patent term means that the invention should not be obvious or apparent to a person of ordinary skill in the field relating to the invention. The invention must contain an inventive step over existing art. It should not be a mere workshop improvement or general re-arrangement of components/features of the invention.

The test for non-obviousness is essential and must be applied from the perspective of a person with ordinary skill in the art (ie, having average skills, and not an expert in that particular technology). While deciding the inventive step, the adjudicator must assess the inventive step on the scale and parameters of a person ordinarily skilled in that art.

In Bishwanath Prasad Radhey Shyam Appellant v Hindustan Metal Industries(2) the Supreme Court of India laid down the importance of assessing inventive step, as follows:

"It is important that in order to be patentable an improvement on something known before or a combination of different matters already known, should be something more than a mere workshop improvement; and must independently satisfy the test of invention or an 'inventive step'. To be patentable the improvement or the combination must produce a new result, or a new article or a better or cheaper article than before. The combination of old known integers may be so combined that by their working interrelation they produce a new process or improved result. Mere collection of more than one integers or things, not involving the exercise of any inventive faculty, does not qualify for the grant of a patent."


Asian Electronics, which owned Patent 193,488 for a 'conversion kit to change the fluorescent lighting units inductive operation to electronic operation', filed a suit for a permanent injunction and damages for infringement against Havells Limited.

The plaintiff alleged that the defendant was using all the unique and important features of its invention. The comparison between the defendant's product and the plaintiff's patented invention was shown as follows:

SNo Claim 1 of Patent 193,488 Defendant's product


Conversion kit



Adaptors on either side of fluorescent lamp



Wiring assembly



Ballast Present, mounted in wiring assembly

The plaintiff submitted that the unique features of the invention were the two adaptors based on two sides, which assist in the process of conversion to electric current from induction and thus minimise the flickering normally associated with fluorescent lights.

The defendant alleged that the plaintiff's invention was not entitled to a patent as it was based on a prior art - US Patent 4246629, which discloses all the essential or important elements of the plaintiff's patent. The defendant further submitted that the plaintiff's patent was just a workshop improvement or a trade variant of the US patent, and lacked the inventive step essential for the grant of a patent under the Patent Act. The defendant cited Section 3 of the act as part of its case:

"Section 3. What are not inventions:
(d) 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 or the mere discovery of any new property or new use for a known substance or of the mere use of a known process, machine or apparatus unless such known process results in a new product or employs at least one new reactant.
(f) the mere arrangement or re-arrangement or duplication of known devices each functioning independently of one another in a known way.


On analysis of the plaintiff's patent, the court stated that the plaintiff was not claiming that any of the components were inventions, or involved a new or inventive step; the patent was claimed for the kit, which incorporated the two sleeve-like ends, one or both of which contained the ballast. In other words, the court concluded that the claim was in respect of only the design for this particular assembly.

The court found that the plaintiff's patent did not disclose any new product or any significant improvement. It was held that the plaintiff's patent was merely a workshop improvement of the US patent. A comparison of the US patent with the plaintiff's was set out as follows.

Embodiment US patent Plaintiff's patent
1. Fluorescent tube Present Present
2. A pair of sleeve-like adaptors on each side of lamp Present Present
3. Wiring assembly Present Present
4. Conversion kit Present Present

Based on this comparison, the court held that the patent could not sustain as it was obvious, and was also subject to Sections 3(d) and 3(f) of the Patents Act.

The High Court relied on the decision reported in British Celanese Ltd v Courtaultds Ltd,(3) in which it was held, of patents involving combinations, that:

"It is accepted as sound law that a mere placing side by side of old integers so that each performs its own proper function independently of any of the others is not a patentable combination, but that where the old integers when placed together have some working interrelation producing a new or improved result then there is patentable subject matter in the idea of the working inter relation brought about by the collocation of the integers."

The High Court observed that the US patent clearly mentioned two ends and an electronic ballast as claimed by the plaintiff in its patent. Further, the function of the end product was the same (ie, a fluorescent lamp). As the plaintiff also failed to explain any significant improvement in function or efficiency, or any objective material in the new product, it was concluded that the patent was hit, prima facie, by anticipation.

In view of the above findings and precedents, the court dismissed the application for the grant of an injunction, stating that the patent was anticipated by prior art and the plaintiff had failed to establish the balance of convenience in its favour.

For further information on this topic please contact Manoj K Singh at Singh & Associates by telephone (+91 11 4666 5000), fax (+91 11 4666 5001) or email (manoj@singhassociates.in).


(1) IA No 8205/2009 in CS(OS) 1168/2009.

(2) AIR 1982 SC 1444.

(3) 1935 (52) RPC 171.

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