The scope of the exclusive right pertaining to a patent is delimited by the (granted) patent claim(s). The exclusive right extends to all technical devices which possess the features specified in the claim. It is irrelevant what other features the devices or methods may or may not possess. The owner of a granted patent has the right to bar others from using devices with the claimed features, but no right to bar anyone from using devices with some, but not all, of the claimed features.
Patent claims have a problematic dual role in the advancement of the public and private benefits of patenting. The applicant’s private benefit requires that the claimed scope be as broad as possible. Breadth is determined partly by the generality of the terminology in the claim (e.g. “a vehicle” is a more general term than “a car”) and partly by the number of claimed features. Each added feature F shrinks the scope because it excludes all devices which do not possess F. The applicant would therefore preferably claim a patent by specifying as few features as possible using the most general terminology possible.
However, the public benefits of the patent system require that the scope of each granted patent should not be too broad. Scopes are limited by granting patents only to patent claims which meet the criterion of inventive step. A typical patent application proceeds from an initial version with very broad claims to a restricted version where the definitions given in the claims have either been increased in number or amended with a more detailed terminology based on the cited objections.
The public benefits of the patent system also require that the scope of each granted patent should be clear and that every patent application should be informative. Clarity reduces legal disputes and costs. Clear and informative patent publications are potentially useful source material for further technological development, whereas unclear publications are not.
It is evident from my previous post that the inventive step criterion can be quite complicated when it is explored in detail. Clarity is often considered a simpler concept than inventive step because the difference between a clear and an unclear technical feature is not assumed to be problematic. Another reason why lack of clarity is not always judged very strictly is that it raises the bar for inventive step, at least in principle. If some of the claimed features are ambiguous or unclear, patent examiners are advised to consider them as broadly as possible. In the absence of better objections, a distant objection D to inventive step can therefore sometimes be raised when a claimed feature F is so unclear or ambiguous that it can be interpreted to correspond with the device disclosed in D. This is sometimes possible even though D on the whole may be quite different from the claimed device and could not have been considered an objection had feature F been clear.
However, even though lack of clarity in a patent claim slightly increases the likelihood of rejection due to lack of inventive step, this is not a sufficient discouragement against deliberate obfuscation. After all, lack of clarity isn’t just a result of an inappropriately general terminology in feature F. The examiner usually has to be both imaginative and lucky to discover distant objections D which happen to correspond to the claimed feature simply because the feature is ambiguous. Furthermore, if no other objections are available, the search for D may take an inordinate amount of time and the objection may be easily circumvented in the next round of the examination.
In view of the above, patent criteria which concern clarity and sufficient disclosure (which are very closely linked, so I will simply label them the “sufficiency criterion” below) are required to protect the public benefits of the patent system. However, unlike the inventive step criterion, a sufficiency criterion has not been formalized in European patent practice. Examiners, boards of appeal and courts only apply vague general guidelines concerning how sufficiency should be judged. In brief, these guidelines refer merely advise the examiner / board member / judge to consider whether or not the content of the claims would be clear to a person skilled in the art, and that’s it.
Objective technical problems revisited
I propose that the sufficiency criterion should be formalized in the same manner as the inventive step criterion. It can be done in a very similar way. In the following presentation I will draw on the problem-solution approach which I discussed in my previous post.
The important insight of the problem-solution approach as it applies to inventive step is that the claimed invention may actually solve a different prior art problem than the applicant assumed. In other words, the applicant’s view of the prior art may be, and often is, incomplete. The risk of granting patents to deliberately obfuscated claims would be greatly reduced if this same insight were to be applied also to the sufficiency criterion. Sufficiency should not depend on the applicant’s own view of the invention and its relation to prior disclosures, but on the true state of the prior art.
The reason why some applicants deliberately obfuscate their patent claims is that even a weak argument for inventive step can be made to appear if the subject matter is unclear across the broad. Ambiguous technical terms which are not elaborated in the description are useful for obfuscation because it is never certain how such terms are delimited, that is, which real-world component fall into under this term and which do not. The applicant may nevertheless argue that the meaning is certain. Patentability examinations and infringement proceedings then become an uncertain game of equivocation, where the meaning of the term can be shifted based on the required arguments.
Of course every examiner recognizes that there is a limit to the degree of ambiguity that a claimed term can have if the claim is to be granted. Obfuscating applicants try to push the proceedings as close to that limit as possible. Obfuscating applicants typically possess large numbers of obscure applications. Most of them may be rejected in patentability examination, but some of them will not. The ones that are granted can be very valuable to the applicant if a reasonable case for infringement can be built. Lack of clarity again facilitates infringement attacks.
The public benefits of the patent system are clearly harmed by deliberate obfuscation. The limit between clear and unclear terms, supported or unsupported features, cannot be marked with any consistency from case to case if the sufficiency criterion is internal. If the sufficiency criterion is internal, patent applicants can use the ambiguous vocabulary which surrounds an ambiguous technical term to describe a putative technical effect which solves a putative technical problem. It can be hard for an examiner to maintain that the claimed feature is too ambiguous if it is supported by a description which has the outwardly appearance of a proper technical problem and solution.
Clarity and sufficient disclosure must therefore be judged against some other yardstick than the application itself. Instead of having examiners assess whether or not the person skilled in the art would be able to carry out the invention as described by the applicant based on the information given in the description, the sufficiency criterion should be that a person skilled in the art is able to carry out the invention as it is manifested over the closest prior art, based on the description given by the applicant.
This means that applicants would no longer be allowed to support the scope of their claims merely through their subjective understanding of the invention. Let’s assume that a patent application A1 specifies a patent claim which includes features F1, F2, F3 and F4. F1 and F2 form the preamble of the claim, while F3 and F4 form the characterizing part. The first component of the sufficiency criterion should be that the applicant must identify in the description a prior art document upon which this division of features is based. In other words, the applicant must disclose a document D1 which discloses features F1 and F2. Citations requirements for prior art documents known to the applicant should be enforced much more rigorously than most patent offices do today.
Lets assume that no closer prior art document than D1 is discovered in the patentability search. The corresponding sufficiency analysis would also ask what the combined technical effect of features F3 and F4 is. In other words, what beneficial or different result, not achieved in D1, is obtained with features F3 and F4? The analysis continues by asking what corresponding technical problem the person skilled in the art would have had to solve, starting from an apparatus which contained only features F1 and F2 (when reading the application text on its earliest priority date), to achieve the technical effect over D1.
This may seem like a minor technical problem. After all, the person skilled in the art is thought to be reading the application text itself, where the solution should be directly disclosed. However, the gist of the sufficiency analysis is that the technical effect must be conceived in its detailed form A, that is, as a detailed description of the changes which take place in the apparatus/method itself, and/or in the surroundings on which it operates, due to F3 and F4 (see the earlier essay). This differs from inventive step analysis, where only the general description of the technical effect may be included in the technical problem. The information given in the application must be so detailed that the skilled person can in a straightforward manner see where the technical effect in its detailed form (a form which may not itself be disclosed in the application) originates.
Just like in inventive step analysis, the subjective technical problem presumably corresponds to the objective problem when no better prior art document than D1 is discovered. And just like in inventive step analysis, the sufficiency analysis will be more or less of the standard kind when this is the case. In other words, the analysis could be carried out just about equally well even without invoking formal problem-solution analysis.
However, the situation is markedly different if the applicant included both features F3 and F4 in the characterizing parts of the patent claim but, as it turns out, feature F4 was in fact known from another prior art document D2, which was unknown to the applicant. This means that only F3 contributes to the technical effect. The requirement of a sufficient disclosure now becomes that F3 and its consequences be described in such detail that the objective technical problem relating to this (detailed) technical effect over the prior art should be solvable for a skilled person from the application text A1.
The utility of this problem-solution approach to sufficiency, again in direct parallel to how the problem-solution analysis tests inventive step, comes from the fact that the number of claimed features not disclosed by the prior art determines how broad the objective technical problem will be. If, in the above example, none of features F2, F3 and F4 would be disclosed by the closest prior art document, then the corresponding technical effect would usually (even in its detailed form) be a lot more general than if just feature F3 distinguishes the claimed invention from the prior art.
It is, and should be, harder for the application to meet the sufficiency criterion if only F3 separates the claim from the prior art. The technical effect of just one feature is necessarily more particular than the technical effect of two or three features. In order for the description to provide sufficient support for a lone distinguishing feature F3, the technical content of this feature must be described in such detail, in the terminology must be shared with document D2 to such an extent, that the person skilled in the art would see where the technical effect comes from.
This does not mean that the applicant would have been required to foresee this technical effect when writing the application. On the contrary. Just as a new argument for inventive step can be introduced in problem solution analysis once the closest prior art has been reliably established, new arguments for sufficiency can also be introduced when the closest prior art is known. What is required from the description of a patent application is that every claimed technical feature must be described in such detail, and linked to such an established vocabulary, that the skilled person can recognize the technical consequences of the feature even in situations which may not have been described in the application.
What does all this have to do with obfuscation? A typical obfuscating patent application is self-contained in the sense that it seeks to link ambiguous technical terms and explanations to each other in a pseudo-consistent manner without linking them to any established scientific or technical vocabulary.
A certain degree of self-containment is to some degree unavoidable in most applications due to the generality of the protection sought with a patent claim. The description therefore has to be a kind of dictionary for all technical terms used in the claims because their meaning in a particular application may differ from their regular meaning. In other words, the dictionary of a patent claim does not necessary have to conform either with general-purpose dictionaries or with the lexicon of other patent applications in the same field.
However, insofar as new meanings are introduced for a technical term T, the description should be an unambiguous dictionary to that meaning. It should contain examples and links which establish a connection between the term T and established technical, scientific and regular vocabularies. This facilitates a clear yes-or-no categorization between objects that correspond to term T and objects which do not correspond to it.
The problem-solution method described in this essay puts the description to the test. Depending on how many of the claimed features are disclosed in the closest prior art document, the bar for sufficient disclosure is either raised, lowered or kept unchanged compared to the amount of detail that the applicant deemed sufficient when writing the application. The question is: has the applicant nevertheless presented enough details about the feature(s), and linked it so clearly to established vocabularies, that the person skilled in the art would recognize the technical effect?