The PCT Rule 13 and specifically the Rules 13.1 and 13.2 gives to the applicant a general guide on how to interpret the unity of invention related to a PCT international patent application. This general rule will also have an influence on how to draft an international application (claim scope and if one or more applications will be needed) and, of course, will influence the fees that the applicant will have to pay to the ISA to receive the ISR (Chapter I) and, if the option is made by the applicant, the further fees related to the IPEA (Chapter II).
It is important to stress that each country or region has its own approach to the unity of invention requirement, and in some cases one would have further examples and explanations about the possibilities to the Patent Examiner to avoid the request of additional payment of fees for the search and written opinion based on the possibility of considering the connected subject matter of a linked group of inventions, as for example in the USA. Also, if you consider the Brazilian Patent Guidelines, you will find an openness for an interpretation on behalf of the unity of invention consideration that will be focused on a broader interpretation to consider different features (even when not directly connected).
Requirement
The international application shall relate to one invention only or to a group of inventions so linked as to form a single general inventive concept (“requirement of unity of invention”).
Circumstances in Which the Requirement of Unity of Invention Is to Be Considered Fulfilled
Where a group of inventions is claimed in one and the same international application, the requirement of unity of invention referred to in Rule 13.1 shall be fulfilled only when there is a technical relationship among those inventions involving one or more of the same or corresponding special technical features. The expression “special technical features” shall mean those technical features that define a contribution which each of the claimed inventions, considered as a whole, makes over the prior art.
For example, see the USPTO explanation “The decision in Caterpillar Tractor Co. v. Commissioner of Patents and Trademarks, 650 F. Supp. 218, 231 USPQ 590 (E.D. Va. 1986) which held that the Patent and Trademark Office interpretation of 37 CFR 1.141(b)(2) as applied to unity of invention determinations in international applications was not in accordance with the Patent Cooperation Treaty and its implementing regulations. In the Caterpillar international application, the USPTO, acting as an International Searching Authority, had held lack of unity of invention between a set of claims directed to a process for forming a sprocket and a set of claims drawn to an apparatus (die) for forging a sprocket. The court stated that it was an unreasonable interpretation to say that the expression “specifically designed” as found in former PCT Rule 13.2(ii) means that the process and apparatus have unity of invention if they can only be used with each other, as was set forth in MPEP § 806.05(e).” Where even in the 80s the interpretation should be flexible on behalf of the applicant, concluding that “Unity of invention exists only when there is a technical relationship among the claimed inventions involving one or more special technical features. The term “special technical features” is defined as meaning those technical features that define a contribution which each of the inventions considered as a whole, makes over the prior art. The determination is made based on the contents of the claims as interpreted in light of the description and drawings.” See https://www.uspto.gov/web/offices/pac/mpep/s1850.html.
We next see the item 3.122 of the Brazilian PTO Patent Examination Guidelines (Part I): “An application that presents several classifications referring to its independent claims do not necessarily indicate that there is no unity of invention. There should be a practical and comprehensive consideration of the degree of interdependence of flexible inventions, in relation to the state of the art revealed by the search report”. Available in Portuguese at https://www.gov.br/inpi/pt-br/assuntos/patentes/consultas-publicas/arquivos/diretriz_de_exame_de_patente_retificado_original_1.pdf.
Further the EPO Guidelines is clear about the relevance of considering the applicant’s position about the absence of need of payment of extra fees for additional minimum search work when addressing the item 6.4 related to dispensing with further search fees.
The importance of the flexibility on the interpretation is based on the need of an approach in favor not only of the applicant’s interests relating to the full access of the international patent protection, but also based on the public interest as stated by the JPO Guidelines of unity of invention. If the ISA starts to be too narrow with the interpretation of the unity of invention requirement, it will be not in compliance with the international patent system goals as stated by the TRIPs Agreement and the mentioned PCT Rules 13.1 and 13.2.
Based on the openness of the unity of invention concept and the mentioned statutory international rules, it is advisable that the PCT ISA Examiner should have a broader interpretation of the unity of invention on behalf of the applicant’s interests of having only one invention with a predictable prosecution of the PCT International Phase Application with specific official search fees and examination fees expected to be paid.
This is especially stressed here – “This was so particularly if the concepts of the inventions were very close and none of them required a search in different classification units, so that the search could be performed for all the inventions without creating too much extra work (see PCT Search Guidelines as agreed upon by the Interim Committee for Technical Cooperation at its seventh session in Geneva in October 1977, PCT/INT/5). In such a case, no objection of lack of unity should be raised because charging further fees would be incompatible with the principle of equity vis-à-vis the applicant (see G 1/89, OJ 1991, 155; see also e.g. T 755/14).” Available at: https://new.epo.org/en/legal/case-law/2022/clr_ii_b_6_4.html.
In the second paragraph of Chapter 3 (Patent Act article 37) of the JPO Guidelines, unity of invention is stated that “(…) the application procedures become simplified and rationalized to the applicant and it becomes easier for third parties to use patent information and transact rights. In addition, it allows the Patent Office to examine such inventions together in an efficient way.”. Available at https://www.jpo.go.jp/e/system/laws/rule/guideline/patent/tukujitu_kijun/document/index/02_0300_e.pdf.
Article 7 of the TRIPs Agreement states: “The protection and enforcement of intellectual property rights should contribute to the promotion of technological innovation and to the transfer and dissemination of technology, to the mutual advantage of producers and users of technological knowledge and in a manner conducive to social and economic welfare, and to a balance of rights and obligations”.