Patent bar Written description, enablement and claims (35 U.S.C. 112) question: original disclosure contains nothing else on materials

Patent barWritten description, enablement and claims (35 U.S.C. 112)

An original specification describes a bracket made of 'steel'. During prosecution, the applicant amends claim 1 to recite 'a bracket made of a metal alloy' and adds the phrase 'or other metal alloys' to the specification. The original disclosure contains nothing else on materials. How should the examiner treat the amendment?

A Enter the amendment, because steel is a metal alloy so the broader term is supported
B Require a terminal disclaimer for the broadened claim
C Object to the new matter and reject claim 1 under 112(a)
D Reject claim 1 under 112(b) as indefinite
E Enter the amendment, because applicants may broaden claims freely before allowance

Show the answer and explanation

Answer: C. Object to the new matter and reject claim 1 under 112(a)

Answer: Object to the new matter and reject claim 1 under 112(a). 35 U.S.C. 132(a) prohibits introducing new matter by amendment. Disclosing a single species (steel) does not necessarily describe the genus (metal alloys). The examiner objects to new matter added to the specification and rejects claims that rely on it under 112(a) (MPEP 2163.06, 608.04). Why not the others: - Steel is an alloy: a species does not automatically support a genus. - Free broadening: broadening is allowed only within what the original disclosure supports. - 112(b): the defect is lack of support, a 112(a) issue. - A terminal disclaimer: it addresses double patenting, not new matter. Rule: New matter in the specification is objected to; claims relying on it are rejected under 112(a). Source: MPEP § 608.04, § 2163.06 (9th ed., Rev. 01.2024); 35 U.S.C. 112(a), 132(a); as at Oct 2026

Common mistake

Thinking a disclosed species supports any genus that contains it.

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Original study material written from the MPEP; not a question from the current exam.Independent. Not affiliated with or endorsed by the USPTO. Verify figures and rules against current guidance before relying on them.