Claimed Invention’s Economic Significance Can’t Be Established: Madras HC Affirms Rejection Of IIT-M's Patent Application On ‘Method Of Doping Potassium Into Ammonium Perchlorate’

The Madras High Court affirmed the rejection of patent application of Indian Institute of Technology, Madras (IIT-M) on ‘Method Of Doping Potassium Into Ammonium Perchlorate’, saying that the economic significance of the claimed invention cannot be established.

IIT, Madras filed a civil miscellaneous appeal under Section 117-A of the Patents Act, 1970, praying to pass an order granting a patent and to set aside the order of The Controller of Patents & Designs refusing registration and a direction that its application be allowed to proceed to grant on an expedited basis.

A Single Bench of Justice Senthilkumar Ramamoorthy said, “… I conclude that without any experimental data to compare the costs of using filtrate material, which requires frequent changing, vis-a-vis using an external reagent, the economic significance of the claimed invention cannot be established. Because of these reasons, I conclude that the claimed invention lacks an inventive step under Section 2(1)(ja) of the Patents Act.”

The Bench noted that the claimed invention must disclose a practical application and should be capable of being exploited for commercial benefit without significant difficulty and that the possibility of doing so must be discernible from its specification and common general knowledge.

Advocates T.K. Ramkumar and Sumitha Vibhu appeared for the appellant while Deputy Solicitor General Rajesh Vivekananthan appeared for the respondents.

Facts of the Case -

IIT-M i.e., the appellant assailed the order by which the patent application was rejected by the Indian Patent Office. It filed the said application entitled ‘METHOD OF DOPING POTASSIUM INTO AMMONIUM PERCHLORATE’ in 2013 and the same was published in 2015. The First Examination Report (FER) was issued in 2018 which raised objections on the grounds that the claimed invention lacks novelty, inventive step, and was patent-ineligible as per Section 3(d) of the Patents Act. The appellant filed a response in 2019, amending the complete specification and then the hearing letter was issued, maintaining objections under Sections 2(1)(ja) and 3(d) of the Act.

In 2020, the order was passed whereby the Controller refused the application under Sections 2(1)(ja), 3(d), and 3(a) (i.e., invention is frivolous) of the Act, the last being a new ground not raised either in FER or even in the hearing notice. Against this backdrop, the appeal arose. The counsel for the appellant submitted that the claimed invention relates to a method of doping potassium into ammonium perchlorate (AP) for increased burn rates in solid propellants used in defence and space applications. When potassium is doped with ammonium perchlorate through a recrystallization process, he submitted that it changes the latter’s thermal properties and has an incremental effect on the solid propellant's burning rates.

The High Court in the above context of the case observed, “The last aspect I examine is whether the claimed invention possesses an inventive step. … in order to surmount the inventive step test test, the claimed invention must possess both the following characteristics: (i) it must exhibit technical advancement as compared to the existing knowledge or have economic significance in the industry or both of the above; and (ii) the purported technical advance must not be obvious to a person skilled in the art.”

The appellant claimed that the inventive step of the claimed invention lies in eliminating the use of external reagents through the usage of the filtrate material, viz., stainless steel sieve or cotton cloth or filter paper wherein varying percentage weights of potassium gets doped into AP resulting in RAP with incremental thermal properties. In this regard, the Court said that even assuming that such usage constitutes a 'technical advance', it must not be obvious to PSITA for it to qualify as 'inventive step'.

“The crucial second step in conducting the obviousness analysis is to identify the notional person skilled in the art (PSITA). The claimed invention relates to the preparation of potassium doped AP for enhancing the burn rates in composite solid propellants. This requires knowledge and expertise in the use and impact of chemical compounds in propellant systems. Therefore, a chemical engineer working in the field of composite solid propellants would qualify as the PSITA for conducting the obviousness analysis”, it added.

The Court further noted that recrystallization of AP enables the doping of potassium in it. After dissolving the AP in distilled water, it is exposed to the potassium present in the filtrate material and the type of filtrate material used and the time of exposure of the AP solution to the filter determine the amount of potassium that gets doped into the AP after recrystallization.

“Turning to the appellant's contention that the usage of the filtrate material in lieu of external reagents constitutes an inventive step, D1 discloses and common general knowledge dictates that floating impurities are removed through the filtration process which inevitably requires the usage of filtrate material. In the claimed invention, the doping of potassium into AP after recrystallization that has accretionary effects on AP's burning rates happens in-situ during the filtration process. The claimed technical advance of choosing the type of filtrate material used therein from and out of known filtering materials would be obvious to PSITA from D1 and common general knowledge”, it also observed.

The Court enunciated that the burn rates of AP increase only till the weight percentage of potassium in AP is around 0.19, and that there is only a marginal impact on the burn rate at higher weight percentages and thus, the appellant's intervention in the process is confined to the extent of limiting the time of exposure of AP to the filter to reach the ideal weight percentage of 0.19 and choosing the type of appropriate filtrate material which only entails routine experimentation and does not require any ingenuity on part of the appellant.

“… the rejection of the claimed invention by the Controller in the impugned order on the basis of Section 3(a) and on industrial applicability under Section 2(1)(j) is held to be untenable, whereas the rejection on the basis of Sections 3(d) and 2(1)(ja) is sustained”, it concluded.

Accordingly, the High Court dismissed the appeal and affirmed the rejection of patent application.

Cause Title- Indian Institute of Technology (IIT Madras) v. The Controller of Patents & Designs and Ors. (Neutral Citation: 2024:MHC:2264)

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