Can Article 34 Amendments introduce new matter into the application?

No, Article 34 Amendments are not permitted to introduce new matter into the application. This is explicitly stated in MPEP 1893.01(a)(3):

“The fact that an amendment made to the international application during the international phase was entered in the national stage application does not necessarily mean that the amendment is proper. Specifically, amendments are not permitted to introduce ‘new matter’ into the application. See PCT Article 34(2)(b).”

If an examiner determines that an amendment introduces new matter, they will require its removal and may make necessary rejections to the claims, following the same procedure as for regular U.S. national applications filed under 35 U.S.C. 111(a).

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Tags: article 34 amendments, new matter, patent examination, PCT