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On Drafting of Patent Application with Parameter-defined Product Claims

Yuning WANG
Chinese Patent Attorney
In a patent application, out of the purposes such as to distinguish the claimed product from a prior product and/or to strive for a reasonable scope of protection, the applicant may use parameter-defined product claims. In view of the scientific development nowadays, the characterizing means has been enriched, resulting in diverse expressions of a parameter feature which enrich the expression of parameter-defined product claims.
The Guidelines for Patent Examination approves the legitimacy and legality of parameter-defined product claims in Section 3.2.2 of Chapter 2, Part II. However, since the defined parameters cannot intuitively represent the structure/composition of the product, disputes arise in the application of the articles relating to determination of novelty, support by the description, adequate disclosure and clear scope of protection in the prosecution.
Subsequently this article proposes some suggestions for the drafting of patent application with parameter-defined product claims in light of the existing difficulties or disputes occurring in the prosecution with respect to parameter-defined product claims.
1. Describing the definition and the measuring method of the parameter in the specification
For a parameter-defined product claim, the scope of protection depends on the parameter. Therefore, it is very important to clearly define the parameter. If a notification is issued to point out that the parameter is unclear, usually the applicant needs to explain or amend the parameter based on the specification. Thus, failing to adequately specify the concept of the parameter in the specification in the drafting stage will make it difficult to clarify the definition of the parameter during the prosecution.
Even for a common parameter, if the definition or standard is confusing, or if the value of the parameter varies due to different measuring conditions, the specification should specify the definition and/or measuring method. For example, in terms of a parameter relating to hardness, since there is a variety of hardness such as Shore hardness, Rockwell hardness, pencil hardness, indentation hardness, and so on, the standard or the measuring method of the hardness should be specified. For a further example, in terms of a parameter relating to viscosity, since viscosity is highly associated with temperature, the temperature at which the viscosity is measured should be specified.
When an uncommon parameter or a self-defined parameter is used in the claim, usually it is necessary to explain the definition and/or the measuring method of the parameter in details in the specification. In a particular case where a new parameter defined by a mathematical formula involving a plurality of parameters is used to define the claim, it is necessary to describe in the specification the definition and/or the measuring method of each of the parameters, as well as the measurement unit of each of the parameters to be introduced into the formula.
2. Describing the method for obtaining or adjusting the parameter in the specification
In a case where the specification does not describe in details how to obtain the parameter defined in the claims, in particular when the parameter is an uncommon parameter or a self-defined parameter, the examiner will probably question whether the specification contains adequate disclosure on the ground that the public may be unable to implement the patent.
A typical risky drafting manner is to describe in the specification that a parameter x is adjustable based on the type and the proportion of a raw material, and describe in the examples that raw materials resin A and resin B are formulated at a suitable proportion and mixed adequately to obtain a composition, a parameter x of the composition being measured to be y. In fact, the above description fails to specify how the type and the proportion of the raw materials affects the parameter x. If the problem of inadequate disclosure is pointed out during the prosecution, the applicant will find it necessary to argue that it is known in this field how to adjust the parameter x based on how the type and the proportion of the raw materials. However, such argument is hardly convincing, and may even have adverse effect on the argument for the inventiveness.
Therefore, the specification should contain suitable disclosure about the factors affecting the parameter and the method for obtaining the parameter. A practical exemplary improvement to the above description is to specify that the raw material resin A may be a specific type, with examples described, the raw material resin B may be a specific type, with examples described, and specify a specific range of the proportion of the resin A and the resin B, as well as a specific range of the parameter x obtained based on the described type and proportion of the materials; meanwhile, the example may describe that the raw materials resin A and resin B are formulated at a specific proportion indicated by a number and mixed adequately to obtain a composition, a parameter x of the composition being measured to be y.
As further improvement, a plurality of examples of the product may be designed, with different parameters obtained under different manufacturing conditions.
The questioning of inadequate disclosure will be more convincingly eliminated if the specification includes detailed description of the factors affecting the parameter and describes multiple examples exhibiting a regular pattern occurring between the parameter and the raw material or the manufacturing condition.
3. Providing multiple comparative examples in the specification
In the prosecution, usually the novelty of parameter-defined product claims is determined based on the novelty deducing principle. Accordingly, it will be easier to refute novelty rejections if a comparative example corresponding to the cited prior art is described in the specification.
However, it is impossible to predict in the drafting stage what prior art document will be cited during prosecution. Therefore, it is hardly possible that the comparative example is designed just the same as the technical solution disclosed by the cited prior art.
On this basis, the specification may describe a variety of comparative examples failing the parameter feature due to various possible factors, so that even the specification does not include a comparative example that is identical or similar to the prior art, there may be one comparative example comparable with the prior art, thereby deducing that the prior art does not have the parameter feature of the present application based on the data of the comparative example.
Practical experience shows a common case that an earlier application of the same applicant is cited for novelty deducing, especially when there is a great number of prior art documents from the same applicant. Considering this, in designing the comparative example, the applicant may use a product involved in his/her own earlier application as a comparative example.
The foregoing suggestions aim to help you overcome some difficulties occurring due to the parameter-defined product claims during the prosecution by improving the drafting of the patent application. Despite of the foregoing, often the product claims and the specification need further consideration of the technology and the relevant legal terms in view of the technical field and the characteristics of the claimed product.
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