In the patent process, the first step is to submit a patent application. Upon examination, if the particular patent application (parent application) contains more than one invention, the applicant may be required to file a separate divisional application to separate the different groups of inventions. The Convention at the Revision Conference of The Hague in 1925 introduced the said concept provided by Article 4G of the Paris Convention for Protection of Industrial Property whereby, it ensured that in cases of multiple inventions, a divisional application might be filed to benefit the applicant. Therefore, the need for divisional applications giving rise to divisional patents arises from the lack of ‘unity of invention.’ The Patent Cooperation Treaty supports the concept of the unity of invention wherein Rule 13.1 provides that the patent application “shall relate to one invention only or to a group of inventions so linked as to form a single general inventive concept.” The patent offices will examine for unity whenever there is more than one independent claim or when the claims within the application do not fall under the same group. The same principles have been adopted by jurisdiction such as India, the United States of America, Europe & China.
India
Section 16(1) of the Patents Act, 1970 provides for filing divisional patent applications. In India, divisional applications are usually submitted in response to the examination report. The question as to whether an applicant may suo motu file for divisional patents was answered by the IPAB in L.G. Electronics Inc. v. The Controller of Patents & Designs and Others. In this case, the Board rejected the claim that the word ‘or’ must be read as disjunctive in the manner and stated that the interpretation is conjunctive wherein the same would be allowed if there is a lack of unity of invention. Providing unbridled liberty would hamper the entire process of patent examination within the country, as it would result in multiple examinations and re-examinations, which would make divisional patent applications counter-productive.
Europe
Article 76(1) of the European Patent Convention (EPC) provides the requirements of a divisional patent application, and the subject matter must be restricted to the content of the parent application. Article 123(2) of the EPC gives the ‘added matter test’ for the same, where the patent application cannot be amended in a manner that extends beyond the contents of the parent application. However, the Guidelines for Examination in the European Patent Office, allow the applicant to amend the divisional application at any later stage of the examining procedure, for it to meet the requirements of Article 76(1) EPC and the amended application would form the basis of further examination.
The time limit for filing a divisional application is given by Rule 25(1) of the EPC by which an application will be valid as long as the parent application is pending, post the grant of patent a divisional application would be invalid. However, if a second divisional application is filed, then it would not be necessary for the parent application to be pending, provided that the first divisional application is pending.
United States of America
The USA works on a principle of restriction requirement under which the examiner must believe that there is more than one invention in the application, which is prima facie distinct from the other. Primarily, a restriction requirement is when two or more independent and distinct inventions are recited in the claims. Upon examination, the examiner will provide a list of “groups,” which represent the different inventions, and will indicate why they think they are distinct from each other. Based on the same, the applicant would have to choose one claim to move forward with, and the other claims may be filed by way of a divisional application.
Section 201.06 of The Manual of Patent Examining Procedure elaborates on the procedures for the divisional applications. The divisional application forms one of the three sub-parts of the applications arising from parent application, which are namely- Continuation Application, Continuation-In-Part Application & Divisional Application. A Continuation Application allows an inventor to add new claims to a parent application (not the specification given in the parent application), as long as the application hasn’t been approved or abandoned. A Continuation-In-Part Application, on the other hand, allows inventors to include “enhancements” to the original design, i.e., change the specifications that were developed after the parent application was filed. The divisional application is unlike the other two, where it arises primarily due to the objections raised by the examinations based on the lack of unity of invention. In this application, a section of the parent application is merely moved to another application as there is more than one single inventive step. The USA also adheres to the principle that divisional patents must be filed before the grant of a patent of the parent application or before it is considered abandoned. However, the patent applicants may continually submit divisional applications at the U.S. Patent and Trademark Office.
China
Article 42 of Rules for the Implementation of the Patent Law of the People’s Republic of China provides that if an application contains two or more inventive steps, the same may be patentable under divisional applications. The provisions, however, do not allow for the specifications to be changed in the way the Continuation-In-Part Applications work in the United States. If the specifications are to be changed, then a new application has to be filed to the Chinese National Intellectual Property Administration, and the prior application will be deemed to be withdrawn. This process is known as ‘claiming domestic priority.’
Whenever there is a defect in unity, the applicant may file a divisional application on his own accord or as a response to the examiner’s report. In practice, however, a divisional application is usually filed such that a set of more desirable claims can be submitted for the invention contained in a patent application and not just to overcome a defect of unity.
Conclusion
The underlying principle behind divisional patents is to have ‘one patent for one invention.’ However, it is not always necessary that multiple independent claims would still result in need of divisional patents. They may be considered unitary if they are linked in a manner to form a single general inventive step. Most jurisdictions follow the same principle where the patent examiners take the final decisions about divisional patents.
