Can new matter be introduced during ex parte reexamination?

New matter cannot be introduced into the disclosure during ex parte reexamination. The MPEP states:

“35 U.S.C. 305 provides for examination under 35 U.S.C. 132, which prohibits the introduction of new matter into the disclosure.”

If new matter is added to the claims or affects claim limitations, the claims should be rejected under 35 U.S.C. 112, first paragraph, for failing to meet the written description requirement. Amendments to the specification should also be carefully examined to ensure they do not introduce new matter.

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Topics: MPEP 2200 - Citation Of Prior Art And Ex Parte Reexamination Of Patents, MPEP 2258 - Scope Of Ex Parte Reexamination, Patent Law, Patent Procedure
Tags: 35 u.s.c. 112, ex parte reexamination, new matter, Written Description Requirement