Under Indian patent law, one patent application must pertain to one invention only; in other words, there must be unity of invention. Section 10(5) of the Indian Patents Act states that:
“The claim or claims of a complete specification shall relate to a single invention, or to a group of inventions linked so as to form a single inventive concept, shall be clear and succinct and shall be fairly based on the matter disclosed in the specification.”
Therefore, from the aforementioned stand point, it is clear that the claims of a patent application in India should cover a single inventive concept and should consist of one invention only. However, if during prosecution it is observed by the Controller that the patent application (herein after referred to as “parent application”) contains a multiple group of inventions and they do not form such a “single invention concept”, the Controller may require the applicant of said parent application to file one or more divisional applications to segregate the individual inventive concepts therein. Further, the Act also allows an applicant to file divisional applications, if he so desires. But in such an instance the burden shifts on the applicant to prove that there is a plurality of inventions in the parent application.
Divisional patent application(s), as the name indicates, are those patent applications that have been divided from a parent application. These applications are governed by the provisions of Sections 16, 10(5) and 7(1) of the Patents Act 1970.
Sub-Section 1 of Section 16 of the Indian Patent Act states that a person who has made an application for a patent under this Act may, at any time before the grant of the patent, if he so desires, or with a view to remedy the objection raised by the Controller on the ground that the claims of the complete specification relate to more than one invention, file a further application in respect of an invention disclosed in the provisional or complete specification already filed in respect of the first mentioned application.
Sub-Section 2 of Section 16 prescribes that the complete specification of the divisional applications shall not contain any new subject matter over the original application or disclosure. These provisions provide that, a divisional application should not contain any additional subject matter in the complete specification filed in pursuance of the parent application but the subject matter claimed in the divisional application should be distinct from that claimed in the parent application.
Therefore, it is clear from the provisions of Section 16 that an objection of "Unity of Invention" is not a mandatory requirement for filing a divisional application, because such applications can also be filed voluntarily by the applicant, taking a cue from the phrase “if he so desires” from Section 16(1) of the Act.
However, whether a division to an existing parent application is done suo motu or adhering to a relevant objection from the concerned Controller, the prima facie essential criteria are existence of more than one invention in the patent application, particularly identifiable in the claims. Ideally, to file such a divisional application before the Intellectual Property Office (IPO), India, some of the claims should be carved out, and a marked copy revealing such change, should be produced, in the parent.
In case when the division is done corresponding to a relevant objection from the concerned controller, generally any of the office actions mention the claim(s)/ group of claim(s). This may simply be followed to easily render the division legitimate. However, for a suo motu divisional application, to obviate and/ or bypass any objection questioning the legitimacy of said division, from the IPO, India, it should clearly be shown that certain claims are copied from the parent application in the daughter application in ditto.
The matter of a suo motu divisional application was also clarified by the IPAB in Milliken & Company v. Union of India, where it was held that the applicant's second divisional application, which was filed voluntarily without receiving an objection on lack of unity in the first divisional application, was valid. In this case applicant's request for voluntary amendment of claims for adding a new set of claims during prosecution of the first divisional application was disallowed. IPAB held that in the absence of any other efficacious remedy to pursue the scope of the disallowed claims filing of the second divisional application is valid. It is clearly an indication towards suo motu division of an application to allow filing of further application with new set of claims. The IPAB upheld the validity of the voluntary second divisional application, without looking into presence of multiple inventions.
Further, in the case of L.G. Electronics v. Controller of Patents (2011), the IPAB was dealing with a situation whether the filing of a divisional application by an applicant, if he so desires, can be interpreted to mean that an applicant can, on his own, file a divisional application even when claims in the specifications relate to only one invention. L.G. Electronics while quoting Section 16(1) of the Indian Patents Act contented that, “if he so desires” empowers an Applicant an unconditional freedom to file a divisional application even when there is no plurality of distinct inventions or inventive concepts.” In response, the Controller of Patents argued that “The heading of Section 16 reads as “Power of Controller to make orders respecting the division of application.” Further, IPAB also held that “Right to file divisional application indeed rests with the applicant but the power to ascertain its allowability is vested with the Controller” and that, “the existence of a plurality of invention in the patent application is the sine qua non for a divisional application by the applicant whether it is suo motu as to remedy Controller's objection.” The Board further held that the phrase “if he so desires” used in Section 16 is not unconditional and it does not give the applicant an unqualified liberty to file a divisional application even when there is no situation of a plurality of the distinct inventions contained in the mother application. Therefore, a divisional application filed to remedy the objection raised by the Controller regarding unity of invention, can be rectified by filing a divisional application by dividing multiple inventions in the parent application only. The divisional application cannot be used to exercise the revival of subject matter in the parent application that has been abandoned, refused, or withdrawn. Further, the Board also stated that the divisional application shall not be filed with the same set of claims as the parent application.
The IPAB in the case of Esco Corporation vs. The Controller of Patents (2020) and in the case of Procter & Gamble Company v. The Controller of Patents & Designs and National Institute of Immunology v. The Assistant Controller of Patents stated that the claims of the divisional application should only be based on a distinct group of claims already made in the parent application. Therefore, it is clear that additional claim(s) would not be allowed as part of a divisional application. Moreover, it was also held that the claims of the divisional application should not include any subject matter that had been claimed in the parent application, and instead, should be distinct and no similar set of claims must overlap in the parent application.
In the case of Boehringer Ingelheim International Gmbh v. The Controller of Patents, it was observed that the applicant had filed a PCT national phase application (i.e., parent application) in India with 18 claims. However, during prosecution, the applicant had amended the claims thrice. First amendment was done by deleting 15 claims and retaining 3 claims. Second amendment, the Applicant expanded from three Claims to Claims 1 – 11, and in third amendment, the Applicant amended the Claims to 1 to 15, i.e., added four new claims. The Controller refused the parent application u/s 15 rejecting the Amendment No. 1 of the parent application on merits and rejecting Amendment Nos. 2 and 3 u/s 57 & 59 of the Act for going beyond the scope of the originally filed claims asserting that these amendments do not wholly fall within the scope of original filed claims as the original claims were directed to use of DPP IV inhibitor whereas the amended claims were extending the protection to a medicament combination of a DIPP IV inhibitor i.e., “use claims” were amended to “product claims”.
Further, the second and third amendments were, thereafter, sought to be converted into a divisional application. The Controller issued an FER with respect to the instant divisional application and objected to its validity under section 16 of the Indian Patents Act. The Controller provided reasons that the claims of the divisional were already examined and refused in the parent, and therefore the same claims cannot be allowed in another application. In meantime, a pre-grant opposition was also filed with respect to this divisional application. Following this, an opportunity of hearing was offered to the Appellant and a hearing notice was issued, wherein the Controller maintained his stand regarding the validity of the divisional application u/s 16(1) of the Act. After hearing the opponent and the Applicant, the Controller refused the divisional application providing the reason that since the divisional claims had been already examined and refused in the parent application, the same Claims cannot be allowed in another application.
Finally, the matter was referred to High Court, and the Court was of the opinion that a divisional application in the aforementioned case cannot be filed since there was no “plurality of inventions” in the parent application. In the aforementioned case, the original ‘DPP IV inhibitor’ arising out of a Markush formula, in various permutations and combinations describing its use and method for treatment, which is only mentioned in the examples in the specification, cannot be permitted to be claimed as separate product claims in a divisional application, as there were no product claims in the parent application. Clearly, the claims in the parent application only related to method or use claims whereas, the claims in the divisional application concern “products” i.e., medicaments or their combinations. Once the product claims were not sought in the original application and the said products were clearly disclosed in the content of the complete specification, the products ought to be treated as having been disclaimed. Thus, the parent application cannot be interpreted to have included a “plurality of inventions”, i.e., completely new product Claims, patentable by way of a divisional application.
Thus, while proceeding with a divisional application in India, an applicant shall keep in mind that the divisional application shall be filed before the grant of patent over the parent application, parent application shall disclose or teach more than one invention in substance, specification of divisional application shall not disclose a subject matter not covered in the parent application, claims of the divisional application shall be duly supported by the parent specification, the claims of the parent and divisional application shall be distinct, i.e., the divisional application shall not claim a subject matter already claimed in parent application/patent.