table of contents
About the partial design system
What is the partial design system?
Previously, the "articles" covered by the Design Act were tangible objects circulating in the market, and parts of articles that could not be traded independently were not considered "articles" under the Design Act, and designs relating to parts of articles were not protected. However, with the increase in clever imitations that incorporate original and distinctive parts while avoiding infringement of the design as a whole, it became impossible to adequately protect investments, so in a partial revision in 1998, "parts of articles" were newly added as a component of a design, and designs relating to parts of articles (partial designs) were also subject to design registration.
Below, we will provide an overview of the partial design system, focusing on the registration requirements and application documents (application form and drawings) specific to partial designs.
Requirements specific to partial designs
The heading of Article 3, Paragraph 1 of the Design Act stipulates that a person who creates a design that can be used industrially may obtain a design registration for that design.
The following three requirements can be derived from the provisions of the heading of Article 1, Paragraph XNUMX of the Design Act.
(1) It must constitute a "design" under the Design Act ("design eligibility requirements").
(2) The design must be specific.
(3) Must be able to be used industrially
Regarding (1), in the case of a partial design, the "part for which the design registration is sought" must be a part that occupies a certain range within the overall shape, etc. of the article to which the design pertains that can be compared with other designs, that is, a closed area contained within the external shape, etc. of the design. In addition, the boundary between the part for which the design registration is sought and the other parts must be clear.
Regarding (2), in the case of a partial design, the specific contents of ① to ③ below must be directly derived.
① Use and function of the part for which design registration is sought
② The position, size and scope of the part for which the design is to be registered
However, even if the "other parts" are not specified in their entirety, if the position, size and scope of the part for which a design registration is sought can be derived in light of the nature of the article, it will be recognized as a specific design.
③ The boundary between the "part for which the design is to be registered" and "other parts"
Regarding (3), in the case of a partial design, it is not judged whether the part in question can be industrially applied, but whether the whole of the article, etc. related to the design of the applied design satisfies this requirement.
Judgment on similarity between partial designs and publicly known designs
The effect of a design right extends to both the registered design and designs similar to it. Therefore, it is important to determine whether the registered design is similar to other designs.
Decision maker
The entity that makes the decision as to whether a product is similar or not is the consumer (including traders).
The judgment of similarity is largely based on human intuition, but when making this judgment, the subjective viewpoint of the creator is excluded and the judgment is made based on the objective impression of the consumer (including the trader) when observing.
Judgment method
Since a design is an inseparable part of the article, etc. and its shape, etc., there is no similarity in the designs unless the articles, etc. related to the designs of the two contrasting designs are identical or similar.
Therefore, the applied partial design and the publicly known design will be deemed to be similar only if they meet all of the following criteria:
① The use and function of the article, etc. related to the design of the applied design and the publicly known design are identical or similar
② The use and function of the "part for which the design registration is sought" of the applied design and the part corresponding to the "part for which the design registration is sought" of the publicly known design are identical or similar.
③ The position, size, and scope of the “part for which design registration is sought” of the applied design in the overall shape, etc. of the article, etc., and the position, size, and scope of the part corresponding to the “part for which design registration is sought” of the publicly known design in the overall shape, etc. of the article, etc., are the same or within the range common in the field to which the design belongs.
④ The shape, etc. of the "part for which design registration is sought" of the applied design is identical or similar to the part of the publicly known design that corresponds to the "part for which design registration is sought"
(Note) The shape, etc. of the "other parts" will not be considered as the subject of comparison.
In addition, if all of the above items ① to ④ are identical, the two designs will be considered to be substantially identical.
Description of application and drawings for partial design registration
Application details
■ [Partial design] column
The [Partial Design] column is no longer an application item for applications filed on or after May 1, 2019.
■ 【Article related to design】 column
In the column for [Article related to the design], enter the "classification of the article" as a whole. Therefore, for example, if you wish to obtain a design registration for the grip part of a camera, enter "camera". Please be careful not to enter "grip part of the camera" etc.
■ [Description of the article to which the design pertains] section
The use and function of the "part for which design registration is sought" are also important factors in determining whether or not the design is to be registered, so if the use and function of the "part for which design registration is sought" is difficult to understand from the drawings alone, an explanation of the use and function of the part in question should also be provided. (Instead of the explanation, it is also possible to clarify the use and function with a [Reference Drawing].)
In addition, when the [Article to the Design] does not belong to any of the “Classification of Articles” in “Appendix 1,” it is acceptable to include an explanation that can help understand the article, such as the purpose and condition of use of the article, in the same manner as for the whole design.
■【Design Description】Column
If the part for which design registration is sought cannot be identified by the description of the drawing alone, the method of identifying said part should be described in the [Description of Design] column. For example, if the "part for which design registration is sought" is drawn with a solid line and the "other parts" are drawn with a broken line in the drawing, the description should read, "The part shown with a solid line is the part for which design registration is sought." In addition, if the boundary between the "part for which design registration is sought" and the "other parts" is drawn with a dashed line, the description should read, "The dashed line is a line indicating only the boundary between the part for which design registration is sought and the other parts." Similarly, if the "part for which design registration is sought" and the "other parts" are distinguished by color, the description should read, for example, "The part other than the part colored with XX color (a single color not included in the design of the application) is the part for which design registration is sought."
Description of the drawings
It is necessary to make it clear which part of the whole article, etc., the "part for which design registration is sought" is. To do this, draw the "part for which design registration is sought" with a solid line and the "other parts" with a dashed line to identify the part for which design registration is sought. It is also possible to identify the "part for which design registration is sought" by distinguishing the "part for which design registration is sought" from the "other parts" by color, etc.
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Source: "Guidelines for Writing Design Registration Application Documents and Drawings, etc." published by the Japan Patent Office |
Examples of partial designs
Partial designs are a useful system that can protect the distinctive parts of an article, and are therefore widely used. In particular, many partial designs have been obtained in the field of electrical appliances such as mobile phones and televisions.
As an example, the overall design and partial design of an iPhone are shown below.

The image on the left is the overall design, and the image on the right is a partial design, the scope of which covers only the rounded outer parts of the iPhone, excluding the screen and buttons.
The difference between a complete design and a partial design is that while a complete design is drawn using only solid lines, a partial design only uses solid lines for the part you wish to obtain rights to, and uses dashed lines for the rest of the design.
By obtaining a partial design like the one shown in the right figure, even if counterfeit products with visually altered button parts of a mobile phone are sold, the part is indicated by a broken line and is not within the scope of the right. Therefore, if the outer part of the mobile phone is imitated, the sale can be stopped and damages can be claimed based on the design right.
Advantages and disadvantages of partial design
Benefit
- Since registration is sought for the characteristic parts, as long as there are no prior designs that are similar to those characteristic parts, registration will be granted.
- If the overall shape is common, it will be easier to obtain rights by only registering a portion of it rather than the entire shape.
- As long as the distinctive features of the design are similar, it is easy to identify infringing products and to issue injunctions against infringing acts.
Demerit
・The right is not registered for only the distinctive design part, but for a part of the overall design. In other words, the positional relationship of the distinctive part in the overall design, its size, etc. are taken into consideration.
Therefore, for example, even if a certain characteristic part is similar, if its position within the overall design is completely different or its size is completely different, it will not be considered similar and the rights cannot be exercised.
- Compared to when the entire trademark is registered, only the characteristic parts are registered, so the contribution of the trademark to the calculation of damages may be deemed small.
Scope of protection for partial designs
When a partial design is imitated, even if the shape of the rest of the design is completely dissimilar, can it be said to constitute a design right infringement? Some have argued that only the part in question is the independent subject of the right, and that the shape of the rest of the design does not have to be similar. However, case law has held that the part in question is merely an essential part of the entire product, and that the similarity judgment should be made by looking at the shape of the entire product.
Specifically, the court ruled that "the partial design system was enacted out of the need to protect designs relating to parts of articles that are the product of original creation (see Article 2, Paragraph 1 of the Design Act). However, even though it is a part, it is only a part in relation to the overall shape of the base article, so the scope of similarity of a partial design should be determined taking into account not only the shape of the partial design but also the position and size of the entire article" (Heisei 22 (Ne) No. 10014 "Manhole Cover Receiving Frame" Case).
Therefore, even if partial designs are similar to each other, if their positions or sizes within the entire article are completely different, it may not be considered design infringement.
Partial Design and Damages
Since a partial design is a design that covers only a part of an article, in cases where a claim for damages is based on the infringement of a partial design, the courts often consider the degree of contribution of the partial design in determining the amount of damages. In general, the greater the proportion of the part, the greater the degree of contribution, and in the case of a partial design relating to a part that one would not pay attention to when purchasing, the degree of contribution is low.
By combining the system with other design registration systems, such as obtaining a partial design and then obtaining a whole design, or utilizing the related design system, it is possible to broaden the scope of protection and the scope of compensation for damages.
If you are considering registering a design, please feel free to contact us for a cost estimate.
We can provide reliable assistance in protecting your distinctive designs, as well as protecting the brand power and value of your valuable products.