Japan's “Utility Model” system is regulated by the Utility Model Law.

Scope of protection
The Utility Model Law offers protection for "devices" which relate to the shape or construction of articles or a combination of articles. No process or chemical substance including pharmaceutical products is protected. The creation level of utility models does not need to be advanced so highly as patents. Therefore, if an invention does not qualify for patent because of its level of creativity, it could still qualify for utility model.

Examination of Application
Although the Utility Model Law, also, enumerate the requirements for effectiveness, such as (i) industrial applicability, (ii) novelty, or (iii) inventive step (the inventive step standard is more relaxed than that of the patent), utility model rights shall be granted without examining the requirements. Examination is effected only as to whether the application is formally in order and whether the article invention pertaining to the application satisfies fundamental requirements such as not relating to a process or a chemical substance, not detrimental to public order, good morals or public health, etc. Substantive examination is effected only in the course of an invalidation trial. Once a utility model right is registered, anyone may file an invalidation action with JPO asserting that the subject device does not satisfy the requirements.

Limitation to Amendment
Before registration, an amendment to the claims, specification, drawings and abstract can be made within one month from the date of application, and the amendment must be within the matters described in the originally filed claims, specification and drawings. No introduction of new matters is allowed. After the registration, an amendment to the claims, specification or drawings is allowed only one time.

Fee and Duration
Registration fees (at least three years' annuities) must be paid upon filing an application in addition to application fee. The duration of a utility model right is 10 years from the date of application.

Publication
Publication is made only after the registration. After the registration, anyone can inspect application documents of the registered case, and can file an invalidation on it.

Patent Applications Based on Utility Model Registration
A holder of utility model right can file a patent application based on his own utility model registration before lapse of three years from the date of filing of an application for the utility model registration, in condition that he abandons his utility model right.

Infringement Case
A registrant must request an Official Search Report on validity, and must show it to possible infringers, when he warns an infringement of his utility model right. The registrant is allowed to exercise his right only after warning accompanied with the Search Report. In case a plaintiff lost his utility model registration due to a bound decision of an invalidation trial after he warned or he exercised his utility model right against the Search Report on validity, he must compensate defendant's damages caused by the warning or the exercise of his utility model right.