4. Wording the patent claims

It is natural for every patent practitioner, but two general notes be allowed in advance nevertheless:

• The claim serves for the protected subject matter's definition. The more logically "AND"ed features a claim has, the lesser its range of protection.
• The claims have to define the invention's subject matter such that it is limited against the prior art.

4.1. Moment of wording
Some patent practitioners write the description first, then the claims. We recommend starting with the claims and drafting the description thereafter. This is not necessary, but facilitates the conceptual separation into decisive and less decisive elements of the invention and the corresponding construction of the description. 

4.2. Main claim
Ideally, the main claim, respectively every independent claim ought to have a starting subject existing in the prior art together with exactly one further feature, which at least makes this subject matter novel over the prior art, i.e. distinguishes them. 

Also in the two-partite wording of a patent claim as generic term (known) and characterizing part (new), the features in the generic term are part of the definition of the protected subject matter and restrict the claim's range of protection just as much as features in the characterizing part. Infringement procedures do not differentiate between those two claim parts anyway.

Therefore, as little features as possible ought to be taken into the generic term or, more generally, into the definition of what is known from the prior art, and only such ones which are absolutely inevitable for the invention's realization. The shorter claim is the broader claim.

The claim is not a shopping list of protected elements. This is often ignored and the generic term, only describing the prior art, is much too long.

Moreover, there is no reason to already word the claim in the two partite form in the patent application, since the prior art is not completely known at that time. Experience shows that an integral wording leads to more restraint in including features, in particular if they are broken down like in an analysis of features and if technically purposefully connected aspects are not divided into allegedly known and new aspects. During the further examination, after the entire prior art has been disclosed, a two-partite re-wording of the claim may be sensible and is then often explicitly demanded by the Examiners of the EPO, referring to Rule 29 EPC. There is no advantage in making such division already at the time of application.

An example from practice:

"Chloride" was known in the prior art, the invention was "bromide". The genus "halogenide", covering both chloride and bromide, was not known from the prior art. A claim with "halogenide" as the generic term should not be formulated in any case. Since this quasi shortens the step between prior art and invention by representing a generalization as being known which is in fact already a first, possibly decisive, conceptual step to the invention. Such very general generic terms entail a particular danger in the U.S.; there, it is not possible to claim later of such a claim that the chosen generic term had not actually been prior art. One is bound to this representation.

Also for this reason, it is highly recommended to show claims as a functional analysis of features, and not in the old two-partite German form.

Most features in claims are defined by one or more words. Interpretation uncertainties are inherent to them. One can coin new words and try to give these creations a sufficiently broad definition in the description. However, the danger applies that apparently harmless features may entail enormous restrictions and enormous interpretation problems. Therefore, it is recommended to inquire in particular the meaning of technical words which initially appear to be entirely clear.

Examples:

Having drafted the claims, at least every independent claim is to be subjected to three relevant suitability tests. The first test is the infringer test. It inquires whether an infringement of this claim is possible at all. The second test is the range-of-protection test. It is checked whether the definition of the subject matter in the claim is broad enough or whether this claim may be avoided easily. The third test is the verifiability test. Here, it is to be tested whether an infringement of the claim may be legally proven. In detail:

The infringer test

This test is the conceptual experiment of an infringement situation; the who - how - where of the infringement are to be inquired after.

• Who may be the infringer? If, e.g. an infringement of the claim is only possible in a private situation, such a claim's value is questionable.
• Where does the infringement take place? If the infringement necessarily only takes place abroad, or if the claim claims both sides of an intercontinental data transfer, such a claim appears to be of questionable value in a territory.
• How is infringed? Product-by-process and method claims, wherein the indirect method product would be the only infringement, are to be examined particularly exactly.

The scope-of-protection test

In order to obtain as broad a scope of protection for the invention as possible, it is necessary to review a claim as to whether

•  the individual feature is technically at all required for limitation over the prior art;
•  whether the individual feature is defined broadly enough.

Every unnecessary feature ought to be deleted and features with too narrow a wording ought to be defined more broadly. This is true for all features of the claim, as explained above, both for features which are new according to the author's (current) opinion and for features describing the (often alleged) prior art.

The verifiability test:

The possibilities of getting pre-information on infringements are limited in Germany; therefore, it always ought to be checked whether the existence of the examined feature can be verified in the infringement procedure. Possibly, a feature that cannot be verified reasonably, e.g. by a structure resulting from the use of a process, may be replaced by a feature which can be verified more easily, in the example e.g. the structure instead of the method creating it.