Patent bar Patent eligibility and utility (35 U.S.C. 101) question: applicant's claimed perpetual-motion machine

Patent barPatent eligibility and utility (35 U.S.C. 101)

An examiner concludes that an applicant's claimed perpetual-motion machine has no credible utility. Under the MPEP, what other rejection should normally accompany the 101 utility rejection?

A A 102 rejection, because inoperative devices are always anticipated by the prior art
B A double patenting rejection
C No other rejection, because 101 and 112 never overlap
D A 112(b) rejection for indefiniteness
E A 112(a) enablement rejection

Show the answer and explanation

Answer: E. A 112(a) enablement rejection

Answer: A 112(a) enablement rejection. When a claim lacks a specific, substantial and credible utility, the MPEP directs the examiner to also reject it under 112(a), because the 'how to use' prong of enablement cannot be met for an invention without utility (MPEP 2107.01(IV), 2164.07). Why not the others: - 112(b): definiteness is a separate question. - 102: inoperability does not make a device anticipated. - Double patenting: unrelated. - Never overlap: utility and enablement's how-to-use requirement overlap by design. Rule: A 101 utility rejection is accompanied by a 112(a) enablement rejection. Source: MPEP § 2107.01, § 2164.07 (9th ed., Rev. 01.2024); 35 U.S.C. 101, 112(a); as at Oct 2026

Common mistake

Making the utility rejection alone.

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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.