The exclusive right of a patentee to stop others from making or using their invention for a defined period is balanced by the obligation to disclose the invention in detail. It serves two purposes: firstly, after the period of exclusivity ends, others can make and use the invention, and second, the disclosed invention becomes the basis for newer technological developments. Particularly, the patent specification should describe the invention as a whole and the manner and "process of making and using it" sufficient "to enable any person skilled in the art" to which the invention pertains to "make and use" the invention. Accordingly, this so-called "enablement" requirement enforces the "quid pro quo of the patent bargain" by requiring a patentee to teach the public how to practice the claimed invention in exchange for market exclusivity for a defined period of time.
The disclosure of invention is critical in terms of drafting the patent application. Particularly, when an inventor comes up with a new and useful invention, then to obtain a patent, he must disclose the details of the invention in the patent specification that describes the invention's technical aspects, functionality, and potential applications. Further, once the patent application is filed and published, the information about the invention becomes publicly available. The quid pro quo aspect here is that the inventor provides valuable information to society about their invention, contributing to the pool of human knowledge. Furthermore, in exchange for making his invention public, the Patent Office grants the inventor exclusive rights for a limited period, typically 20 years from the date of filing. Thus, these exclusive rights allow the inventor to control who can make, use, sell, or license the patented invention. This monopoly is intended to incentivize innovation by providing inventors with the opportunity to profit from their creations.
Hence, it is mandatory for an inventor to provide enough information in the patent specification, which would allow a person skilled in the art to carry out substantially all that which falls within the ambit of what is claimed in the invention. The disclosure of the best mode of the invention can be demonstrated in the working examples, which would assist the Patent Office in ascertaining the nature of the invention.
Requirement of sufficiency in India
The requirement of sufficiency of disclosure under the Indian Patents Act, 1970 (hereinafter also referred to as 'the Act') has been statutorily laid down in Section 10 of the Act, read with Rule 13 of the Indian Patent Rules 2003. Section 10(4) of the Act provides that any complete specification shall (a) fully and particularly describe the invention and its operation or use and the method by which it is to be performed; (b) disclose the best method of performing the invention which is known to the applicant and for which he is entitled to claim protection; (c) end with a claim or claims defining the scope of the invention for which protection is claimed; (d) be accompanied by an abstract to provide technical information on the invention."
Apart from being a valid objection raised by Patent Controllers during the examination of the patent application, insufficiency also remains a valid ground for opposition and revocation:
Pre-grant Opposition: Section 25(1)(g) of the Patents Act allows any person to file a pre-grant opposition against a pending patent application on the ground that “the complete specification does not sufficiently and clearly describe the invention or the method by which it is to be performed.”
Post Grant Opposition: Section 25(2)(g) of the Indian Patents Act, 1970 allows any person interested to file a post-grant opposition against a granted patent (within one year of the date of grant) on the ground that "the complete specification does not sufficiently and clearly describe the invention or the method by which it is to be performed."
Revocation of Patent: Section 64(1)(h) of the Indian Patents Act, 1970, states that the failure to disclose the ‘best mode’ is a ground for challenging the validity of a patent.
The Indian Patent laws are fairly clear on the requirement; however, in terms of practice, it has been re-emphasized through various orders and decisions issued by the quasi-judicial and judicial authorities, for example:
In the case of Ram Narain Kher v. Ambassador Industries [A.I.R. 1976 Delhi 87], the defendants had argued that the invention had not been adequately described in the patent or sufficiently claimed to bring it within the ambit of the term “invention” under law. While refusing to grant an injunction, the Delhi High Court went ahead and acknowledged the defendant’s objections, saying that the defendants were competent to claim revocation of the patent in terms of Section 64(1) of the Act.
In a pre-grant opposition (filed by Cipla Ltd.) in the patent application no. 396/DEL/1996, having Gilead Science Inc. as the applicant, it was held by the Controller of Patents that: "In order to satisfy the requirement of sufficiency of description, the applicant for patent is under a public duty to satisfy at least following three conditions, namely: complete specification must describe an embodiment of the invention claimed in each of the claims; description must be sufficient to enable those in the industry concerned to carry it into effect without making further invention or experiments; and description must be fair, i.e., it must not be unnecessarily difficult to follow”.
In the case of Tata Global Beverages Limited vs Hindustan Unilever Limited [TRA/1/2007/PT/MUM], the Intellectual Property Appellate Board (IPAB) held that the sufficiency requirement is satisfied even when at least one way of working the invention is clearly described, enabling a skilled person to carry out the invention. The IPAB also ruled that Section 10(4) of the Act does not necessitate disclosing all conceivable ways of operating the invention but only mandates disclosure of the best method known to the applicant.
In a recent judgement passed by Hon’ble Delhi High Court, in the matter of Titan Umreifungstechnik GMBH and Co. KG vs Assistant Controller of Patents and Designs as Anr., redefined the working example requirement in the complete specification. Specifically, the patent application no. 7529/DELNP/2014 was refused on two grounds: (1) non-fulfilment of requirements under section 2(1) (ja) (lack of inventive step) and (2) non-compliance with section 10(4) of the Act (lack of definitiveness and lack of enablement). In case of lack of working examples in the specification, however, the Court held that “primary requirement is that the application includes a clear and complete description of the invention, its operation, use and method by which it is performed so that a person skilled in the relevant field can reproduce the invention based on the description in the application”. The Court also pointed out that the working example requirement differs for chemical and non-chemical inventions. Thus, the Court made clear that there is no mandatory requirement to provide examples for non-chemical related inventions. Accordingly, it was held that the "mere absence of working examples does not render the subject application liable for rejection”.
The requirement of disclosing the invention sufficiently in the patent specification, which should enable a person with average skill and knowledge of the art to be able to replicate the invention to get the claimed results, is a quid pro quo for the grant of a patent. Specifically, the patent specification should disclose the best mode of performing the invention at the time of filing the application. Hence, in order to avoid refusal, opposition or revocation of the patent application, it is recommended to disclose the best method of performing the invention, which is known to the inventor. Further, with evolving jurisprudence and significant decisions, the IPO must consider revisiting practices and manuals by incorporating suitable examples.