Can amending a claim lead to a rejection under 35 U.S.C. 112(a)?

Yes, amending a claim to include an invention not described in the original application can lead to a rejection under 35 U.S.C. 112(a). The MPEP 2174 states: “If a claim is amended to include an invention that is not described in the application as filed, a rejection of that claim under 35 U.S.C. 112(a) or pre-AIA 35 U.S.C. 112, first paragraph, as being directed to subject matter that is not described in the specification as filed may be appropriate.” This is illustrated by the case of In re Simon, where claims to a reaction product of a subcombination were found not to be described in the original application that disclosed a combination.

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Topics: First And Second Paragraphs, MPEP 2100 - Patentability, MPEP 2174 - Relationship Between The Requirements Of 35 U.S.C. 112(A) And (B) Or Pre - Aia 35 U.S.C. 112, Patent Law, Patent Procedure
Tags: 35 u.s.c. 112(a), claim amendments, In Re Simon, new matter, Written Description