Converting patent application to a design application

Converting patent application to a design application　

November 14, 2025
Akihiro Ryuka
Patent Attorney (Japan) / Attorney-at-Law (California)

1. Requirements for Conversion

(1) Timing of Conversion

A patent application may, in principle, be converted into a design application at any time while it is pending examination.
However, conversion is not permitted if more than three months have passed since the date on which the applicant was served with the first Office Action indicating grounds for refusal.

(2) Identity of Applicant

The applicant before and after the conversion must be the same.
If the applicant differs, a change of ownership must be recorded before filing the conversion request.

(3) Design Eligible for Conversion

The design to be converted must be disclosed in the original patent specification and drawings.
The target design must be identical to the design described in the original application documents.

2. Effect of Conversion

Once a patent application is converted into a design application, the resulting design application is deemed to have been filed on the same date as the original patent application.

If, at the time of the original patent filing:

• a Paris Convention priority claim was made, or
• documents for the novelty grace period were submitted,

such documents are deemed to have been submitted to the Japan Patent Office simultaneously with the new design application after conversion.

Furthermore, the original patent application is deemed to have been withdrawn as a result of the conversion.

3. Significance of Converting to a Design Application

Conversion from a patent application to a design application serves as a flexible tool for reconsidering the nature of protection needed.
When design protection is more appropriate than technical protection, the applicant may switch to a design application while maintaining the original filing date.

Conversion may be considered, for example, when:

• An Office Action citing grounds for refusal has been issued against the patent application;
• Changes in business strategy after filing make design protection more valuable.

4. Practical Considerations

(1) Conversion to Full Designs or Partial Designs

Conversion to either full designs or partial designs is permitted.
The following example shows a single patent application converted into multiple partial-design applications:

Patent Application No. 2019-119532 (2019) (Unpublished)
→ Design Registration No. 1654053 (Application 2019-14833 (2019))
→ Design Registration No. 1654027 (Application 2019-14834 (2019))
→ Design Registration No. 1646319 (Application 2019-14827 (2019))

(2) Comparison with Conversion to Utility Model Applications

The Utility Model Act protects technical creations related to structure and shape, whereas the Design Act protects the visual appearance of products.
If the purpose is to protect functional improvements, conversion to a utility model is suitable.
If the goal is to protect aesthetic or design features, conversion to a design application is more appropriate.

(3) Filing Strategy When the Design Is Not Yet Finalized

At the patent application stage, it is effective to include multiple candidate six-view drawings of possible designs.
Prior to requesting examination, the applicant may select only the necessary designs and convert them into design applications.
It is also possible to convert a single patent application into multiple design applications simultaneously.