Obviousness (35 U.S.C. 103)

Obviousness asks whether the claimed invention as a whole would have been obvious to a person of ordinary skill before the effective filing date (AIA) or at the time of invention (pre-AIA). The examiner makes the prima facie case; the applicant answers with argument and Rule 132 evidence.

Patentability: 101, 102, 103 and 1122 min read4 sections

Must-know for the exam

Graham inquiries: scope and content of the prior art, differences, level of ordinary skill, plus objective evidence (MPEP 2141)
KSR rationales include predictable combinations, simple substitution, known techniques, obvious to try and TSM (MPEP 2143)
Analogous art: same field of endeavor, or reasonably pertinent to the inventor's problem (MPEP 2141.01(a))
Overlapping ranges are prima facie obvious; rebut with criticality or teaching away (MPEP 2144.05)
A modification that changes the reference's principle of operation, or makes it unsatisfactory for its purpose, does not support obviousness (MPEP 2143.01)
Attacking references one by one does not rebut a combination; bodily incorporation is not the test (MPEP 2145)
Secondary considerations need a nexus to the claimed features (MPEP 716.01(b))
Unexpected results must be commensurate in scope with the claims and compared with the closest prior art (MPEP 716.02(d)-(e))
Pre-AIA 103(c) removes commonly owned 102(e)/(f)/(g) art for obviousness only; AIA 102(b)(2)(C) removes it for both 102 and 103 (MPEP 2146, 2154.02(c))
Evidence goes in a Rule 132 declaration; attorney argument is not evidence (MPEP 716.01(c))

On this page · 4 sections

Traps that cost marks

Thinking any undisclosed sliver of a claimed range defeats obviousness.
Limiting analogous art to the applicant's own industry.
Arguing that references must cite each other to be combined.
Treating big sales numbers as decisive without tying them to the claimed features.
Expecting results for one embodiment to save a broad genus claim.
Thinking obviousness still requires an express suggestion to combine.
Bringing the inventor's own reasoning into a test about the person of ordinary skill.
Arguing each reference in isolation against a combination rejection.

Building and answering the case

The examiner must account for every claim limitation (MPEP 2143.03) and give a reason, grounded in the evidence, why a person of ordinary skill would have combined or modified the references. Legal precedent (duplication of parts, changes in size or shape, optimizing a result-effective variable) can supply a rationale where the facts fit (MPEP 2144.04, 2144.05).

The applicant can argue that a reference teaches away (criticizes or discourages the claimed solution, not merely prefers something else), that the combination would change a reference's principle of operation, or that secondary considerations (unexpected results, commercial success, long-felt need, failure of others) outweigh the case.

Where to look

When a question turns on a detail you are unsure of, search these sources on the exam computer:

•MPEP 716, 2141-2146, 2158 (9th ed., Rev. 01.2024)
•35 U.S.C. 103
•37 CFR 1.132

Premium

Every note. Every question. One pass.

2 more sections of this note are part of Premium.

Every section of every study note
650+ original questions across every outline topic
Full timed practice exams
A worked explanation on every question
Your full mistake bank and weak-area review

Unlock with Premium

From about US$14.92/mo on the Until-you-pass pass (12 months)

Exam-style questions

← Previous note: Pre-AIA novelty and statutory bars All study notes