What Are the Graham Factors in Obviousness Analysis?

The Graham factors are the four factual inquiries the Supreme Court set out in Graham v. John Deere Co., 383 U.S. 1 (1966), for deciding whether an invention is obvious under 35 U.S.C. § 103: (1) the scope and content of the prior art, (2) the differences between the prior art and the claims, (3) the level of ordinary skill in the art, and (4) secondary considerations such as commercial success and long-felt need.¹ Every patent examiner, court, and review board applying the non-obviousness requirement works through this framework, and it is the structure that decides whether a claim survives a § 103 challenge.

Where the Factors Come From

Section 103 says a patent cannot be obtained if the differences between the claimed invention and the prior art would have made the invention, as a whole, obvious to a person having ordinary skill in the art before the effective filing date.² Two features of that language shape everything downstream. The comparison is to the invention “as a whole,” not isolated components. And the timing anchor is the effective filing date, a benchmark the America Invents Act put in place in 2013 to replace the older “time the invention was made” standard.

The statute also provides that patentability cannot be negated by the manner in which the invention was made.² Whether the inventor stumbled onto the answer or spent a decade chasing it, the only question is whether the result would have been obvious to a skilled person looking at the prior art.

In Graham, the Supreme Court held that § 103 codified earlier judicial precedent and gave the comparison a structure. The three factual inquiries the Court identified, together with the real-world evidence it separately recognized as relevant, are what practitioners now refer to as the four Graham factors.¹

Factor One: Scope and Content of the Prior Art

The first step is mapping what was publicly known before the effective filing date. Under 35 U.S.C. § 102(a), that covers anything patented, described in a printed publication, in public use, on sale, or otherwise available to the public.³ The “otherwise available to the public” phrase reaches broadly. A conference presentation, a YouTube demonstration, or a product sold on a foreign website can all qualify.

Not every reference counts, though. The reference must qualify as “analogous art,” which the USPTO evaluates under a two-prong test. A reference is analogous if it comes from the same field of endeavor as the claimed invention, even when it addresses a different problem. A reference outside the inventor’s field still qualifies if it is reasonably pertinent to the particular problem the inventor was trying to solve.⁴ Satisfying one prong is enough.

This is where obviousness fights often get interesting. An examiner working on a new surgical clamp might pull in a reference from industrial robotics because both involve gripping mechanisms under precise pressure. The applicant’s counter is usually that the reference is not analogous — different field, different problem. But the bar for “reasonably pertinent” is not especially high, and examiners regularly reach across industries.

Factor Two: Differences Between the Claims and the Prior Art

The second inquiry requires a precise, claim-by-claim comparison between what the applicant claims and what the prior art discloses. Examiners give claims their broadest reasonable interpretation consistent with the specification, then lay those interpreted claims alongside the prior art references.⁴ The goal is to isolate which elements or steps in the claim are not found in any single prior art reference.

The comparison treats both the invention and the prior art as a whole. An examiner might find that every structural element of a claimed device exists in Reference A except one fastening mechanism, which appears in Reference B. The question then becomes whether a skilled person would have had reason to combine those references.

This step also demands discipline against hindsight. Once you know the inventor’s solution, it is remarkably easy to find the pieces scattered across the prior art and declare the combination obvious. The Supreme Court has warned against using the patent itself as a roadmap to assemble prior art references after the fact.⁵ Reconstruction is proper only when it relies on knowledge that was within the level of ordinary skill at the relevant time and does not smuggle in insights from the applicant’s own disclosure.⁶

Factor Three: The Level of Ordinary Skill in the Art

The third inquiry sets the lens for the whole analysis: the hypothetical person having ordinary skill in the art, often shortened to PHOSITA. This is not an expert at the cutting edge, and not a layperson. It is a competent practitioner with the education, experience, and awareness of prior art typical for the relevant field at the time of the invention.

The USPTO weighs several factors in defining that skill level:

The types of problems encountered in the field.
How prior art solutions have addressed those problems.
The rapidity with which the technology evolves.
The sophistication of the technology, from simple mechanical assemblies to complex molecular biology.
The educational level of active workers in the field.

Not every factor matters equally in every case, and one or two often predominate.⁴ In fast-moving software, rapidity of innovation and low experimentation cost might set a high baseline. In mature manufacturing, educational level and decades of accumulated solutions might dominate. Getting this definition right matters because a higher skill level makes more combinations “obvious” and a lower one gives the applicant more room.

The PHOSITA is presumed to know all relevant prior art as of the effective filing date. That is a legal fiction. No real person has read every pertinent patent and publication. But the standard makes sure the analysis accounts for the full body of available knowledge rather than what any one individual happened to encounter.

Factor Four: Secondary Considerations

The fourth Graham factor looks beyond the prior art comparison and asks how the real world reacted to the invention. The Supreme Court recognized in Graham that evidence like commercial success and long-felt but unsolved needs could illuminate whether the invention was truly obvious.¹ When timely presented, examiners must consider this evidence in determining obviousness.⁷ It can tip the balance toward patentability even when the prior art comparison initially looks unfavorable.

The Nexus Requirement

Before secondary consideration evidence gets substantial weight, there must be a nexus — a factually and legally sufficient connection between the objective evidence and the specific features recited in the claims.⁸ A product that sells because of its brand or marketing campaign does not prove the patented feature was non-obvious. The commercial success has to flow from the claimed invention itself, not from unclaimed features or external factors.

Types of Secondary Considerations

The most commonly raised categories include:

Commercial success, where strong sales of a product embodying the claimed invention can be attributed to the patented features rather than marketing or brand recognition, and the success is commensurate in scope with the claims.⁹
Long-felt but unsolved need, where the industry recognized a persistent problem and actively sought a solution but failed to find one before the inventor did.¹⁰
Failure of others, documented in attempts by skilled practitioners that fell short before the claimed invention.
Unexpected results, such as performance exceeding what the prior art would have predicted, synergistic effects, or the surprising absence of an expected drawback.¹¹
Skepticism of experts, where recognized authorities in the field doubted the feasibility or effectiveness of the invention before it was made.
Copying by competitors, where others adopt the patented approach rather than designing around it.

These considerations work best when they reinforce each other. An invention that attracted expert skepticism, satisfied a long-felt need, and achieved unexpected results tells a more convincing story than commercial success standing alone.

How KSR Changed the Way the Factors Are Applied

For decades after Graham, the Federal Circuit developed the Teaching-Suggestion-Motivation (TSM) test, which required examiners to find an explicit teaching, suggestion, or motivation in the prior art before combining references. In 2007, the Supreme Court rejected the rigid application of that test in KSR International Co. v. Teleflex Inc., calling it incompatible with precedent when used as a mandatory formula.⁵ KSR broadened the obviousness inquiry and now sits alongside Graham as one of the two cases any patent practitioner needs to know cold.

The Court emphasized that a person of ordinary skill is “a person of ordinary creativity, not an automaton.”⁵ Common sense, market pressures, and design incentives can all supply reasons to combine known elements, without a prior art reference that explicitly proposes the combination. If a skilled person would see the benefit of a predictable variation and could implement it, § 103 likely bars patentability.

After KSR, the USPTO codified several rationales that can support an obviousness finding:

Combining prior art elements according to known methods to yield predictable results.
Simple substitution of one known element for another to obtain predictable results.
Use of a known technique to improve similar devices in the same way.
“Obvious to try” — choosing from a finite number of identified, predictable solutions with a reasonable expectation of success, where there is a design need or market pressure.
Making predictable variations of available work in response to design incentives or market forces.

Each rationale requires explicit factual support, not a conclusory assertion that the combination would have been obvious.¹² Still, the shift from requiring a documented suggestion in the prior art to allowing common sense and ordinary creativity made it substantially easier for examiners to reject claims as obvious.

Using the Factors to Overcome a Section 103 Rejection

The examiner carries the initial burden of establishing a prima facie case of obviousness with facts and reasoning tied to the Graham inquiries.¹³ A typical rejection identifies two or three references, maps each claim limitation to a specific disclosure, and articulates a reason to combine. Once that prima facie case exists, the burden shifts to the applicant. Several responses use the Graham factors directly.

Attack the Combination

Challenge the examiner’s rationale under Factor Two. If the prior art teaches away from the proposed combination, that is powerful rebuttal evidence. A reference “teaches away” when it criticizes, discredits, or otherwise discourages the approach the examiner says would have been obvious.⁶ Simply disclosing an alternative is not enough. The reference must affirmatively steer a skilled person in a different direction.

Another angle: show that the combination would render the primary reference inoperable for its intended purpose. If substituting a component from Reference B into Reference A would break Reference A’s core function, the combination is improper.⁶

Demonstrate Unexpected Results

If the claimed invention produces results a skilled person would not have predicted, that evidence can overcome the prima facie case. The results must be greater than expected to an unobvious extent and must represent a significant, practical advantage.¹¹ Comparative test data submitted through a declaration under 37 C.F.R. § 1.132 is the standard vehicle. Attorney argument does not substitute for actual data.

Present Secondary Considerations

Factor Four is not just for litigation. Commercial success data, evidence of industry skepticism, or documentation of others’ failed attempts can be submitted by declaration during prosecution. The examiner must weigh this evidence against the prima facie case, subject to the nexus requirement.

Amend the Claims

Sometimes the cleanest path is narrowing the claims to recite features that distinguish the invention from the cited references. Adding a limitation that no reference discloses or suggests can eliminate the basis for the rejection entirely. The tradeoff is a narrower patent, but a narrow patent that issues is more valuable than a broad application that never does.

Where Else the Factors Apply

The Graham framework governs obviousness beyond initial examination. It is the central analysis in inter partes review (IPR) proceedings before the Patent Trial and Appeal Board, where obviousness based on prior patents and printed publications is the most common ground for challenging an issued patent. The key procedural difference is the standard of proof. In an IPR, the petitioner must show unpatentability by a preponderance of the evidence, rather than the clear and convincing evidence standard that applies in federal court litigation. That lower threshold makes the PTAB a popular venue for obviousness challenges, and patent owners defending against an IPR generally need strong secondary considerations evidence to hold their claims.

1
Justia U.S. Supreme Court Center. Graham v. John Deere Co. 383 U.S. 1 (1966)
2
Office of the Law Revision Counsel. 35 USC 103 – Conditions for Patentability; Non-Obvious Subject Matter
3
Office of the Law Revision Counsel. 35 USC 102 – Conditions for Patentability; Novelty
4
United States Patent and Trademark Office. MPEP 2141 – Examination Guidelines for Determining Obviousness Under 35 U.S.C. 103
5
Justia U.S. Supreme Court Center. KSR International Co. v. Teleflex Inc. 550 U.S. 398 (2007)
6
United States Patent and Trademark Office. MPEP 2145 – Consideration of Applicant’s Rebuttal Arguments and Evidence
7
United States Patent and Trademark Office. MPEP 716 – Affidavits or Declarations Under 37 CFR 1.132
8
United States Patent and Trademark Office. MPEP 716 – Affidavits or Declarations Under 37 CFR 1.132 – Section: 716.01(b)
9
United States Patent and Trademark Office. MPEP 716 – Affidavits or Declarations Under 37 CFR 1.132 – Section: 716.03(a)
10
United States Patent and Trademark Office. MPEP 716 – Affidavits or Declarations Under 37 CFR 1.132 – Section: 716.04
11
United States Patent and Trademark Office. MPEP 716 – Affidavits or Declarations Under 37 CFR 1.132 – Section: 716.02(a)
12
United States Patent and Trademark Office. MPEP 2143 – Examples of Basic Requirements of a Prima Facie Case of Obviousness
13
United States Patent and Trademark Office. MPEP 2142 – Legal Concept of Prima Facie Obviousness