Medical Device Risk Classification from Class I to IV

1. Key takeaways

The statutory classification in Japan consists of three groups, namely general medical devices, controlled medical devices, and highly controlled medical devices, corresponding to Classes I, II, and III to IV in the international vocabulary. Classification is designated by the Minister of Health, Labour and Welfare by generic name, and applicants have no right of self-assessment. Directly inferring a Japanese class from FDA or CE classification is the leading cause of an entire registration dossier being scrapped, because the underlying standards of judgment differ even when the product looks identical. The scrapped dossier is not merely a cost; it also resets the project calendar, since classification, route, and entity selection all have to be redone in sequence.

• Three statutory names map onto four international risk classes, so the mapping is not one-to-one.
• The standard of judgment in the definitions is the consequence of malfunction, not the use scenario.
• Classification directly determines which type of manufacturing and marketing business license the license-holding entity must hold.

2. Legal basis

The three-way classification and its procedural consequences rest on the following provisions. Each definitional provision names both the risk criterion and the authority that makes the designation.

1. PMD Act Article 2, Paragraph 5: general medical devices, being medical devices for which the possibility of an effect on human life or health in the event of malfunction or similar events is almost nil, designated by the Minister of Health, Labour and Welfare.
2. PMD Act Article 2, Paragraph 6: controlled medical devices, for which an effect on human life or health in the event of malfunction or similar events is possible and which require an appropriately managed status, designated by the Minister of Health, Labour and Welfare.
3. PMD Act Article 2, Paragraph 7: highly controlled medical devices, for which a serious effect on human life or health in the event of malfunction or similar events is possible and which require a specially managed status, designated by the Minister of Health, Labour and Welfare.
4. PMD Act Article 23-2-12: notification for general medical devices; Article 23-2-13: certification for designated items; Article 23-2-5, Paragraph 1: approval for the remainder.
5. PMD Act Article 23-2, Paragraph 1: the manufacturing and marketing business license is divided by class into the first, second, and third types.
6. The current statute: Act No. 145 of 1960 (Showa 35), as revised by Act No. 84 of 2013 (Heisei 25), promulgated November 27, 2013, effective November 25, 2014.

3. Expert insights

Insight one: the standard in the three definitions is the consequence of malfunction, not the use scenario.

Article 2, Paragraphs 5 through 7 use the formulations that an effect is almost without possibility, that an effect is possible, and that a serious effect is possible. The anchor of judgment is the severity of consequences in a failure state, which is related to, but does not fully correspond with, whether the product is invasive or implantable. It is not rare in Japan for products with the same function to be placed in different classes because their structural designs differ, which is precisely why borrowing a foreign class label fails. The design details that decide the outcome are often invisible in a marketing brochure, and only a close reading of the structure against the definitional wording reveals them.

Insight two: the statutory names and the international classes do not map one to one.

There are only 3 statutory names, while the international risk vocabulary has 4 classes. Highly controlled medical devices cover both Class III and Class IV, so within the Japanese statutory text itself it is impossible to distinguish Class III from Class IV by name; the distinction must be recovered from the generic name listings and the public classification information published by PMDA. Any internal document that writes a Japanese class as a single number has already made an unsupported leap.

Insight three: classification directly determines the license type of the license-holding entity.

Article 23-2, Paragraph 1 divides the manufacturing and marketing business license into the first, second, and third types, tied to the classification of the devices dealt in. When appointing a designated manufacturing and marketing business operator (D-MAH), the project must verify that the operator’s license type covers the target item; where the license type does not cover it, the application fails at the formal stage before any substantive review begins. Screening the operator’s license type at the selection stage costs one conversation; discovering the gap after filing costs the project a full resubmission cycle.

4. Practical recommendations

• Output the classification judgment in writing with a source screenshot or link attached. Record three parts: the generic name, the classification, and the basis of designation.
• Determine the license-holding entity only after the class is fixed. Use the class to screen candidate D-MAHs by license type first, avoiding agreements signed before the coverage problem is discovered.
• Remain skeptical of products that look like Class I. Products carrying measurement functions, energy output, or software algorithms are placed into the controlled categories in Japan more often than a Chinese manufacturer’s intuition would suggest.
• Judge each model individually when one product has multiple models. Differences between models can change the assessment of failure consequences and thereby change the classification.

5. Verification checklist

• □ Has the statutory name to which the target generic name is designated been confirmed in an official listing?
• □ Has it been confirmed that the license type of the candidate license-holding entity covers that classification?
• □ Has the intuitive inference that Class III equals certification been avoided, replaced by verifying the existence of a certification standard?
• □ For multi-model products, has the classification judgment been completed model by model?
• □ Does the internal comparison table note the mapping between the 3 statutory names and the 4 international classes?

Regulatory information verified as of October 29, 2026.

How GRZAN can help. GRZAN provides medical device and IVD registration, quality system, in-country representative and local testing support for the Japanese market. Our team manages PMDA submissions across Shonin/Todokede routes, coordinates J-QMS conformity, and supports post-market vigilance obligations. Business enquiries: info@grzanglobal.com