Utility model protection is limited to devices relating to the shape or structure of an article or combination of articles. Therefore, pharmaceutical products, materials, chemical substances, food products, software are not protectable subject matter under a utility model registration. Unlike a patent, a method, such as product management or a manufacturing process and a product claimed as a result of a process are not protectable subject matter under a utility model.

The term of utility model protection is 10 years.

Please refer to the following site:
https://www.ondatechno.com/en/news/utility-models/p519/

First of all, methods, pharmaceutical products, materials, and chemical substances are not protectable subject matter for utility model registration.

The utility model application is registered without examination.  When you would like to enforce the utility model, it is necessary to obtain a Registrability Report.  The Registrability Report is issued based on public domain documents.  There are oftentimes more reasons for invalidation than the information in the Registrability Report.  It is risky to enforce the utility model without thorough research.  Because, if the Japan Patent Office thereafter concludes that the utility model registration should be canceled, the registrant has the responsibility to compensate the infringer for any damages incurred by the registrant because of any warning and enforcement action by the registrant. Further, unlike a Patent case, the burden of proof is on the registrant, not the infringer, and is responsible for preparing documentation to prove the validity of the utility model registration. Therefore, if the registrant cannot prove the validity of its enforcement action, the registrant is liable for the damages incurred by the infringer.

For further information, please see:
Enforcement of Utility Model Rights
https://www.ondatechno.com/en/news/utility-models/p519/

The utility model marking must be deleted on products upon the expiration of the registered utility model.  Please note that violation of prohibition of false marking lead to imprisonment with labor not exceeding one year or to a fine not exceeding 1,000,000 yen.

Please refer to Japanese Utility Model Law, Article 52 (Prohibition of False Marking) and 58 (Offense of False Marking)

No. The applicant must choose to enter the Japanese national phase either as a patent application or as a utility model application.

In addition, note that it is not possible to enter the Japanese national phase of a PCT application as a design application, although it is available as a patent and/or utility model application.