New Matter and “Final” Office Actions in Japan: Amendment Limits Under Article 17-2 — What You Can Still Change

Foreign counsel handling a Japanese Office Action are often surprised twice: first that an amendment which would be routine at home is refused as new matter, and then that after a “final” Notice almost nothing can be changed. Both come from one provision — Article 17-2 of the Patent Act — which sets when amendments may be made, what they may contain, and how narrow they must be at the final stage. This article sets out the rules in the order they bite.

1. When Amendments Are Allowed (Art. 17-2(1))

The description, claims and drawings may be amended at any time before the decision to grant is served — except that once a Notice of Reasons for Refusal has been received, amendments are allowed only (i) within the period designated in the first Notice, (ii) within the period designated in a notice under Art. 48-7, (iii) within the period designated in the last Notice where a further Notice was issued, and (iv) together with the filing of an appeal against a decision of refusal. Outside these windows the claims are frozen.

2. The New-Matter Test (Art. 17-2(3))

Every amendment must stay within the matters described in the description, claims and drawings as originally filed (for a foreign-language application, the translation, or the original where a corrected translation is filed). The Guidelines phrase the test as whether the amendment introduces a new technical matter relative to the technical matters a skilled person would derive from the original disclosure as a whole. Consequences for practice:

• Intermediate generalisation — lifting one feature out of an embodiment and claiming it without the features it was disclosed with — is the classic new-matter finding
• Numerical ranges not disclosed as such are risky even if the endpoints appear separately
• Correcting an obvious error, or clarifying wording whose meaning is evident from the original, is not new matter

3. The Unity-Shift Rule (Art. 17-2(4))

When claims are amended after a Notice, the invention examined in that Notice and the invention as amended must still form a group satisfying the unity requirement of Art. 37. Replacing the examined invention with a different one that shares no special technical feature — a “shift amendment” — is not permitted; the proper vehicle for a different invention is a divisional application.

4. After a Final Notice or With an Appeal: the Four Permitted Amendments (Art. 17-2(5), (6))

5. Dismissal of Amendment (Art. 53) and Its Consequence

Where an amendment made after a final Notice, or together with an appeal, breaches Art. 17-2(3) to (6), the examiner must dismiss it by a reasoned written decision (Art. 53). No separate objection lies against the dismissal; it can be contested only within an appeal against the decision of refusal (Art. 53(3)). In practice a dismissed amendment means the application is judged on the claims as they stood before, so a final-stage amendment should be drafted to be clearly within one of the four categories.

6. Strategy: First Response Versus Final Stage, and the Divisional Route

Because the first Notice is the only stage at which the claims can be reshaped freely (subject to new matter and unity), the first response should already contain the fallback positions — dependent claims drawn to the features most likely to distinguish, so that a later final-stage amendment can be a simple limited restriction to one of them. Where a different claim scope is needed after the final stage, file a divisional application within the windows of Art. 44 rather than fight the amendment limits. For the argument side of an Art. 29(2) rejection see our inventive step guide; for deadlines, the Office Action hub.

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