By Jigyasa Pareek

In Kemin Industries Inc. vs The Controller of Patents [CMA(PT) No.46 of 2024], the Madras High Court set aside the refusal of patent application number 201617013577, entitled “Use of Ferulic Acid Esterase to Improve Performance in Monogastric Animals”, and directed that the application be granted. The Controller had refused the application on the grounds of lack of inventive step in view of prior art documents D1 and D2, and non-patentability under Sections 3(d) and 3(i) of the Patents Act, 1970.  

The subject application claimed a method of reducing, by a specified percentage, the main chain degrading enzymes necessary to extract metabolizable energy from animal feed. The method involved supplementing feed formulated for monogastric animals with ferulic acid esterase (FAE) produced from bacteria, in combination with four main chain degrading enzymes, namely cellulase, xylanase, glucanase and amylase. The purpose was to extract metabolizable energy efficiently from animal feed.

The complete specification disclosed experimental data: Table 1 set out the enzymatic activity of prototype I (amylase, xylanase, cellulase and glucanase); Table 7 presented comparative data showing the release of ferulic acid from feed under different conditions: use of (i) FAE alone, (ii) the prototype enzyme mixture alone, (iii) the combination of prototype with FAE, and (iv) the control group. The data revealed that the combination of prototype I with FAE released significantly higher levels of ferulic acid than any of the other groups, indicating more efficient breakdown of non-starch polysaccharides (NSPs).

The data also established that the animals fed with this formulation showed a markedly lower feed conversion ratio (FCR), meaning that less feed was required to achieve the same or higher growth in animals. Notably, although better growth and performance was an outcome of the invention, the focus of the invention was on the method of extracting metabolizable energy more efficiently from animal feed.

While the individual use of xylanase, cellulase and glucanase in breaking down NSPs in feed was already known, the particular combination of these three enzymes with amylase and FAE was not known. The Appellant argued that this selection was not obvious, particularly as xylanase differs structurally from the other three enzymes, and that the synergy of the chosen enzymes produced unexpected results.

The Controller defended the refusal on three counts:

• Obviousness in View of Prior Arts (Section 2(1)(ja)): D1 disclosed the combination of FAE with xylanase. The Controller argued that even though the claimed invention used four main chain degrading enzymes together with FAE, Table 1 of the complete specification showed that xylanase displayed the highest enzymatic activity among the four enzymes, thereby suggesting that the inventive contribution lay only in what was already known from D1. D2 was argued to contain similar teachings.
• Mere Use of a Known Process (Section 3(d)
• Method Amounted to Treatment of Animals (Section 3(i)): According to the Controller, the claimed process was a method of treatment of animals intended to increase their economic value. In support of this interpretation, reliance was placed on the Madras High Court’s earlier decision in Kymab Limited vs Assistant Controller of Patents & Designs (2024:MHC:3498), and it was emphasised that a proper reading of the complete specification revealed that the method was centred around fattening poultry fed with the formulation.

The insights provided by Madras High Court into the patentability of the invention are as follows:

Section 3(i) of the Patents Act

Section 3(i) contains two limbs: the first limb pertains to forms of treatment of human beings and the second limb relates to processes for a similar treatment of animals. The Court noted that the monopoly claim in the subject application was directed at a method of extracting metabolizable energy more efficiently from animal feed using FAE supplemented with the four enzymes. This, the Court clarified, could not be characterised as a method of treating animals, either as illustrated in Kymab or otherwise. Accordingly, the Court held that the claimed invention was not excluded from patent protection under Section 3(i).

The Court opined that if the claims had pertained to a method of administering a drug or feed to an animal to fatten it and increase its economic value or that of its products, the bar of Section 3(i) would have applied. However, Section 3(i) cannot be extended to cover a method of supplementing animal feed simply because its use may ultimately result in improving the economic value of the animal or its products. The Court held that “Section 3(i), which is intended to exclude from patent protection any process for the treatment of human beings or animals (albeit for the three purposes mentioned therein) so as to sub-serve the underlying public policy of not permitting monopoly-based barriers to methods of treatment, is not designed to exclude from patent protection inventions like the claimed invention.”

Section 3(d) of the Patents Act

Section 3(d) contains three limbs: first two limbs deal with known substances and the third limb relates to the mere use of a known process, machine or apparatus. This provision has an inbuilt exemption filter that if the known process results in a new product or employs at least one new reactant, it would not be excluded from patentability.

In the instant case, the Controller had concluded that the claimed invention was a mere discovery of a known process, relying on documents D1 and D2. The Court, however, found that the process claimed in the subject application was not disclosed in D1 or D2.

• Regarding D1, the Court noted that while it taught the combination FAE with xylanase, it did not disclose or suggest supplementation with the other three main chain degrading enzymes (amylase, cellulase and glucanase) that were integral to the claimed invention.
• Regarding D2, the Court noted that it only taught the use of FAE with a single polysaccharide-modifying enzyme selected from a group that included xylanase, glucanase, arabinase, a pectinolytic enzyme, and a rhamnogalacturonase. D2 neither disclosed a combination of enzymes as claimed in the subject application, nor did it claim any unexpected results by the use of such combination.

On this basis, the Court concluded that the claimed invention was in respect of a new process.

Inventive Step

In assessing inventive step, the Court examined the experimental data disclosed in the specification. The data demonstrated lower feed conversion ratio (FCR) and increase in animal body weight, thereby supporting the claim of increased efficiency in extracting metabolizable energy. This technical data evidenced a synergistic effect arising from the combination of the four enzymes with FAE. Coupled with the finding that the cited prior arts (D1 and D2) neither disclosed this specific combination nor demonstrated the unexpected results, the Court concluded that the claimed invention was not obvious to a PSITA and thus involved an inventive step.

In view of the foregoing, the impugned order was set aside and the patentability of the subject invention was upheld.