Patent bar Written description, enablement and claims (35 U.S.C. 112) question: reads The fastener of claim

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

Claim 1 recites 'a fastener comprising a threaded shaft made of titanium'. Claim 2 reads 'The fastener of claim 1, wherein the shaft is made of a metal.' What is the proper treatment of claim 2?

A Reject it under 112(d), because it fails to further limit claim 1
B Allow it, because a dependent claim is proper if it refers to an earlier claim
C Object to it as a duplicate of claim 1 once both claims are allowed
D Reject it under 112(a) for lack of enablement
E Reject it under 102 as anticipated by claim 1

Show the answer and explanation

Answer: A. Reject it under 112(d), because it fails to further limit claim 1

Answer: Reject it under 112(d), because it fails to further limit claim 1. 35 U.S.C. 112(d) requires a dependent claim to specify a further limitation of the subject matter claimed. 'Metal' is broader than 'titanium', so claim 2 does not further limit claim 1; the examiner rejects it under 112(d) (MPEP 608.01(n)(III)). Why not the others: - Any reference makes it proper: the claim must also narrow. - Anticipated by claim 1: a claim is not prior art against another claim of the same application. - Duplicate objection: claim 2 is not identical; it is broader, which is a 112(d) issue. - Enablement: nothing suggests the disclosure fails to enable a metal shaft; the defect is the claim's form. Rule: A dependent claim that broadens or merely repeats its parent violates 112(d). Source: MPEP § 608.01(n) (9th ed., Rev. 01.2024); 35 U.S.C. 112(d); 37 CFR 1.75(c); as at Oct 2026

Common mistake

Treating any claim that refers back as a valid dependent claim.

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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.