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6.3.8.6.2 Inventive Step

Date Published

Also in this Chapter:​​​​​​​​​​​​​​

Key Legislation:

Patent Cooperation Treaty (PCT):

  • Article 33 The International Preliminary Examination 

Regulations under the PCT:

  • Rule 65 Inventive Step or Non-Obviousness

PCT ISPE Guidelines:

This issue may arise in one of the following ways [Art 33(3) Rule 65]:

  • where lack of novelty has been raised against a particular claim, an inventive step objection relying on the same citation will be automatically applicable. In such instances it will generally be unnecessary for examiners to undertake a detailed analysis of the inventive step issue with regard to that claim.
  • where a claim is considered to be novel, but is considered to lack inventive step in view of a particular citation in combination with common general knowledge, appropriate explanation will be required.
  • where a claim is considered to lack an inventive step in view of an obvious combination of two or more citations, appropriate explanation will be required.

The issue of inventive step, in relation to any claim defining the invention, is whether in light of one or more prior art documents it would have been obvious to the person skilled in the art to arrive at something falling with the scope of the claim.  The word “obvious” suggests that it does not go beyond the normal progress of technology, but merely follows plainly or logically from the prior art.

When assessing whether the requirement of inventive step or non-obviousness is met, individual documents or combinations of such documents may be considered.

Note: Examples of inventive step objections are provided in Annex I - Examples of Inventive Step Objections and further information regarding the appropriate categorisation of documents used in inventive step objections is provided in 6.1.12.5.2 Citation Category

Document Plus Common General Knowledge - No Documentary Evidence Required (single source of information)

An inventive step objection may be taken in view of the disclosure of a single prior art document.  Examples of this situation include:

i. where a technical feature known in a technical field is applied from its original field to another field and its application therein would have been obvious to a person skilled in the art;

ii. where a difference between the document’s content and the claimed matter is so well known that documentary evidence is unnecessary;

iii. where the claimed subject matter relates to the use of a known product, and the use would have been obvious from the known properties of the product;

iv. where the claimed invention differs from the known art merely in the use of equivalents that are so well known that the citation of documentary evidence is unnecessary.

In determining whether a feature is so well known that documentary evidence is unnecessary, examiners should consult with the 3 person team (see 6.1.8.4 Search Considerations).  Note however that where the feature can be readily found in a text book or other document, then this source should be cited.

For further information see PCT/GL/ISPE/12 at Appendix A13.13.

Document Plus Common General Knowledge – Documentary Evidence Required (the document/s used to support an assertion of CGK are categorised as “A”)

An inventive step objection may be taken in view of the disclosure of a single prior art document combined with common general knowledge where documentary evidence is used to demonstrate the common general knowledge. This case arises in situations similar to those noted above in items i – iv, where the difference between a document’s content and the claimed matter is considered to be obvious in light of common general knowledge but further support for this assertion in the form of documentation is warranted.

In determining whether a feature is so well known that documentary evidence is required, examiners should consult with the 3 person team (see 6.1.8.4 Search Considerations).

Combining Documents (Mosaicing multiple documents where all documents are categorised as “Y”)

In considering whether there is inventive step as distinct from novelty, it is permissible to combine the teachings of two or more prior art references, for example, different published patents, or several teachings contained in the same prior art reference, such as one particular book, but only where such combination would be obvious to the person skilled in the art. In determining whether it would be obvious to combine the teachings of two or more distinct documents, the examiner should have regard to each of the following [PCT/GL/ISPE/12 at para 13.12]:

i. whether the nature and content of the documents are such as to make it likely or unlikely that the person skilled in the art would combine them;

ii. whether the documents come from similar or neighboring technical fields and if not, whether the documents are reasonably pertinent to the particular problem with which the invention was concerned.

In regard to item i. above, if two documents could not in practice be readily combined because of an incompatibility in the disclosed features essential to the invention, then combining the documents should not normally be regarded as obvious.  For example, the incompatibility could be if a proposed combination, substitution or modification of a prior art document would render the prior art unsatisfactory for its intended purpose, or would change the principle of operation of the prior art invention.

It is noted that combining teachings of documents does not necessarily involve an ability to combine their specific or physical structures.  The important consideration is what the combined teachings of the documents would have suggested to the person skilled in the art.

Furthermore, the combining of old elements in the prior art without changing their functions, or to take advantage of their known functions, can be regarded as obvious.  The prior art would implicitly suggest this and therefore the claimed invention would not be inventive.

Paragraph 13.13 of the PCT ISPE Guidelines specifies the practices of combining teachings for inventive step considerations:

“The combination, substitution or modification of the teachings of one or more items of prior art may only lead to a lack of inventive step/obviousness where a person skilled in the art would have been motivated by the prior art or his general knowledge, with a reasonable likelihood, to combine, substitute or modify one or more items of prior art.

Conversely, where such combination could not have been expected from a person skilled in the art, the requirement of inventive step (non-obviousness) would be met, even if each single item would have been obvious if taken individually.

The combining of two or more parts of the same document would be obvious if there is a reasonable basis for the person skilled in the art to associate these parts with one another. It would normally be obvious to combine with other prior art documents a well-known text book or standard dictionary; this is only a special case of the general proposition that it is obvious to combine the teaching of one or more documents with the common general knowledge in the art. It would, generally speaking, also be obvious to combine the teachings of two documents, one of which contains a clear and unmistakable reference to the other. It should be noted that the motivation to modify the prior art teachings need not be the same as the applicant’s. It is not necessary that the prior art suggest the combination to achieve the same advantage or result discovered by the applicant. The prior art may suggest the claimed invention, but for a different purpose or to solve a different problem.”

In relation to the phrase “would have been motivated by the prior art or his general knowledge”, there are three main sources for a reason, suggestion, motivation or desire to combine documents:

i. the nature of the problem to be solved;

ii. the teachings of the prior art that either explicitly or implicitly suggest the claimed invention in the documents themselves; or

iii. the knowledge generally available to one of ordinary skill in the art.
That knowledge cannot come from the applicant’s invention itself or by hindsight analysis by reading the applicant’s own invention into the prior art.  

The phrase “with a reasonable likelihood” indicates that there is a reasonable expectation of success, or at least some degree of predictability.  For example, whether the prior art reveals that in making or carrying out the claimed invention, those of ordinary skill would have a reasonable expectation of success.

When taking an inventive step objection based on a combination of documents (mosaic), examiners must provide detailed reasoning as to why it would be obvious to the person skilled in the art to combine the teachings of the documents.  Examples of an appropriate level of detail are given in Annex I - Examples of Inventive Step Objections​​​​​​​.

Problem-Solution Approach According to PCT Guidelines

Inventive step may also be assessed using the problem-solution approach, which consists of the following stages:

  1. Determine the closest prior art.  The closest prior art is that combination of features derived from a single reference that provides the best basis for considering the question of obviousness.  In practice, the closest prior art generally relates to a similar product or process and requires the minimum of structural or functional modifications to arrive at the claimed invention.
  2. Establish the objective technical problem to be solved.  This involves studying the claimed invention, the closest prior art and the difference between the two in terms of features (structural and functional), and then formulating the technical problem.  The technical problem derived in this way may not be what the application presents as “the problem,” as the objective technical problem is based on objectively established facts, in particular those appearing in the relevant prior art, which may be different from the prior art that the applicant was aware of at the time the application was filed.

    The objective technical problem must be formulated without pointers to, or elements of, the technical solution offered by the invention.  To do so would necessarily result in ex post facto analysis.

    In some instances, the objective technical problem can be viewed as an aggregation of a plurality of partial problems.  Where the invention is a solution to a plurality of independent “partial problems”, then it may be necessary to separately assess, for each partial problem, whether the combination of features solving the partial problem is obvious.  In each separate assessment a different document can be combined with the closest prior art for each partial problem.
  3. Consider whether or not the claimed invention, starting from the closest prior art and the objective technical problem, would have been obvious to the person skilled in the art.  Particular consideration should be given to whether there is any teaching in the prior art as a whole that would (not simply could) prompt the skilled person, faced with the technical problem, to modify or adapt the closest prior art, thus arriving at the claimed invention.

Note: The requirement of technical progress is not a requirement for the problem-solution approach. Nevertheless, an objective problem can always be formulated using the problem-solution approach (“finding an alternative”, “making it easier to manufacture”, “cheaper to manufacture”) even in the case where there is no technical progress.

See also PCT/GL/ISPE/12 at Appendix to Chapter 13.

For further guidance on inventive step see also:

Amended Reasons

Amended Reason Date Amended

Published for testing
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