Every case cited in MPEP §§ 2141–2141.03 | Plain-English Rewrites + Exam Takeaways
Each case entry gives you:
Cases are organized to match how the MPEP is structured. When a question tests §103, the examiner works through these questions in order:
MPEP § 2141 | The big-picture rules every §103 question rests on
What the examiner is looking for: Whether the claimed invention as a whole would have been obvious to a person of ordinary skill before the effective filing date. The examiner must (1) make specific factual findings using the Graham factors, (2) articulate a clear reason why the art would be combined, and (3) not rely on hindsight from the applicant's own disclosure.
MPEP § 2141; § 2141.02
Short story: The Supreme Court was asked how obviousness should be determined under the 1952 Patent Act. The patent involved a clamp device for farm plows. Rather than just looking at whether the patent was new, the Court laid out a four-factor test that every examiner must walk through.
Rule: Every §103 obviousness analysis must address all four Graham factors:
Memory hook: "Scope → Differences → Skill → Secondary." These four never go away, even after KSR.
MPEP § 2141 — Graham v. John Deere Co., 383 U.S. 1, 148 USPQ 459 (1966)
"As reiterated by the Supreme Court in KSR, the framework for the objective analysis for determining obviousness under 35 U.S.C. 103 is stated in Graham v. John Deere Co., 383 U.S. 1, 148 USPQ 459 (1966). Obviousness is a question of law based on underlying factual inquiries. The factual inquiries enunciated by the Court are as follows:
(A) Determining the scope and content of the prior art; (B) Ascertaining the differences between the claimed invention and the prior art; and (C) Resolving the level of ordinary skill in the pertinent art.
Objective evidence relevant to the issue of obviousness must be evaluated by Office personnel. Such evidence, sometimes referred to as 'secondary considerations,' may include evidence of commercial success, long-felt but unsolved needs, failure of others, and unexpected results."
"The Graham factors were reaffirmed and relied upon by the Supreme Court in its consideration and determination of obviousness in the fact situation presented in KSR, 550 U.S. at 406-07 (2007). The Supreme Court has utilized the Graham factors in each of its obviousness decisions since Graham. As stated by the Supreme Court in KSR, 'While the sequence of these questions might be reordered in any particular case, the [Graham] factors continue to define the inquiry that controls.'"
MPEP § 2141; § 2143
Short story: Teleflex held a patent on an adjustable gas pedal that included an electronic sensor at a particular location. KSR sold a similar adjustable pedal. Teleflex sued for infringement. The Supreme Court found the patent obvious. The key issue: the Federal Circuit had been requiring that examiners find an explicit written "teaching, suggestion, or motivation" (TSM) in the prior art before combining references — the Court said that was too rigid.
Rule: The TSM test is valid but cannot be applied in an overly rigid way. Obviousness is a flexible inquiry that also includes: common sense, known techniques applied to known problems, obvious-to-try reasoning (when there are a finite number of predictable solutions), and market-driven incentives. The "combination of familiar elements according to known methods" that "yield predictable results" is likely obvious.
The four errors the Federal Circuit made (testable!):
Memory hook: "KSR loosened the TSM leash — predictable combinations are obvious."
MPEP § 2141 — KSR International Co. v. Teleflex Inc., 550 U.S. 398, 82 USPQ2d 1385 (2007)
"The Supreme Court in KSR reaffirmed the familiar framework for determining obviousness as set forth in Graham v. John Deere Co., 383 U.S. 1, 148 USPQ 459 (1966), but stated that the Federal Circuit had erred by applying the teaching-suggestion-motivation (TSM) test in an overly rigid and formalistic way. KSR, 550 U.S. at 404. Specifically, the Supreme Court stated that the Federal Circuit had erred in four ways: (1) 'by holding that courts and patent examiners should look only to the problem the patentee was trying to solve'; (2) by assuming 'that a person of ordinary skill attempting to solve a problem will be led only to those elements of prior art designed to solve the same problem'; (3) by concluding 'that a patent claim cannot be proved obvious merely by showing that the combination of elements was "obvious to try"'; and (4) by overemphasizing 'the risk of courts and patent examiners falling prey to hindsight bias' and as a result applying '[r]igid preventative rules that deny factfinders recourse to common sense.'"
"[T]he Supreme Court reaffirmed principles based on its precedent that '[t]he combination of familiar elements according to known methods is likely to be obvious when it does no more than yield predictable results.' The operative question is thus 'whether the improvement is more than the predictable use of prior art elements according to their established functions.'"
"When a work is available in one field of endeavor, design incentives and other market forces can prompt variations of it, either in the same field or a different one. If a person of ordinary skill can implement a predictable variation, § 103 likely bars its patentability. For the same reason, if a technique has been used to improve one device, and a person of ordinary skill in the art would recognize that it would improve similar devices in the same way, using the technique is obvious unless its actual application is beyond his or her skill."
MPEP § 2141
Short story: Adams invented a battery using magnesium and cuprous chloride electrodes — a combination the prior art had specifically warned against, saying it would be too dangerous. The combination turned out to have remarkable properties that experts had not predicted. Even though both materials were individually known, the resulting combination was NOT obvious because experts would have been led away from it.
Rule: Even when both elements are individually known, a combination is not obvious if the prior art taught away from that combination, or if the combination produced unexpected results beyond what the references would have predicted.
Memory hook: "Adams Battery — known parts, unexpected interaction, non-obvious." This is the counter-example to KSR's "predictable combination" rule.
MPEP § 2141 — United States v. Adams (cited in KSR, 550 U.S. at 416)
"The Court recognized that when a patent claims a structure already known in the prior art that is altered by the mere substitution of one element for another known in the field, the combination must do more than yield a predictable result."
The KSR Court cited Adams to illustrate: even if two elements are individually known, their combination is not obvious when (1) the prior art taught away from that combination, or (2) the combination produced unexpected results. These principles are "instructive when the question is whether a patent application claiming the combination of elements of prior art would have been obvious."
MPEP § 2141
Short story: A paving machine combined a radiant heat burner (already used in paving) with an asphalt spreader (also already known). The combination didn't create any new effect — the burner still did what burners do, and the spreader still did what spreaders do. The Court held it was obvious.
Rule: When existing elements are combined and each element merely performs the same function it always performed, and there is no new or synergistic result, the combination is obvious.
Memory hook: "Black Rock — no synergy, no surprise, obvious."
MPEP § 2141 — Anderson's-Black Rock, Inc. v. Pavement Salvage Co., 396 U.S. 57, 163 USPQ 673 (1969) (cited in KSR, 550 U.S. at 416-17)
"In Anderson's-Black Rock, Inc. v. Pavement Salvage Co., [t]he two [pre-existing elements] in combination did no more than they would in separate, sequential operation."
The KSR Court used Anderson's-Black Rock to illustrate the principle that "[t]he combination of familiar elements according to known methods is likely to be obvious when it does no more than yield predictable results." Where each element performs its known function without any synergistic result, the combination is obvious.
MPEP § 2141
Short story: A dairy farmer patented a water-flush barn-cleaning system. Each component (water tanks, slanted floors, drains) was old. The combination just arranged known elements, and each part still did exactly what it always did. The Supreme Court found it obvious.
Rule: Arranging old elements in a new combination, where each element still performs its known function and there is no synergistic interaction, is obvious.
Memory hook: "Sakraida Barn — old parts, same functions, new arrangement = obvious."
MPEP § 2141 — Sakraida v. AG Pro, Inc., 425 U.S. 273, 189 USPQ 449 (1976) (cited in KSR, 550 U.S. at 417)
"[I]n Sakraida v. AG Pro, Inc., the Court derived ... the conclusion that when a patent simply arranges old elements with each performing the same function it had been known to perform and yields no more than one would expect from such an arrangement, the combination is obvious." KSR, 550 U.S. at 417 (internal quotations omitted).
The Graham factors were also applied in Sakraida — it is one of the three post-Graham Supreme Court decisions cited in KSR as illustrating the doctrine that predictable combinations of known elements are obvious.
MPEP § 2141
Short story: A method patent for managing bulk HTML email campaigns was challenged as obvious. The Federal Circuit confirmed that examiners may use common sense to supply a missing limitation from the prior art — but common sense must still be supported by evidence and a reasoned explanation, especially when the missing element goes to the heart of the invention.
Rule: Common sense can be invoked to fill a gap in the prior art, but it must be supported by a reasoned explanation. It cannot be used as a bare conclusory assertion to sweep away a key limitation.
Memory hook: "Common sense needs a reason — not just a wave of the hand."
MPEP § 2141 — Perfect Web Technologies, Inc. v. InfoUSA, Inc., 587 F.3d 1324, 1329, 92 USPQ2d 1849, 1854 (Fed. Cir. 2009)
"At the time [of the decision in In re Lee], we required the PTO to identify record evidence of a teaching, suggestion, or motivation to combine references because '[o]mission of a relevant factor required by precedent is both legal error and arbitrary agency action.' However, this did not preclude examiners from employing common sense. More recently [in DyStar Textilfarben GmbH v. C.H. Patrick Co., 464 F.3d 1356, 1366 (Fed. Cir. 2006)], we explained that use of common sense does not require a 'specific hint or suggestion in a particular reference,' only a reasoned explanation that avoids conclusory generalizations." Perfect Web, 587 F.3d at 1329 (citations omitted).
MPEP § 2141
Short story: Apple argued that a "common sense" rationale supported combining references to reject claims related to linking phone numbers in documents to phone applications. The Federal Circuit pushed back, clarifying that common sense cannot be used without evidence and a reasoned explanation, particularly when the missing limitation is central to the claimed invention.
Rule: Common sense must still be "supported by evidence and a reasoned explanation" — particularly where the missing limitation goes to the heart of the invention. This is the limit on using common sense to combine.
Memory hook: "Arendi — the guardrails on common sense in a combination rejection."
MPEP § 2141 — Arendi S.A.R.L. v. Apple Inc., 832 F.3d 1355, 1363, 119 USPQ2d 1822, 1827 (Fed. Cir. 2016)
"… we conclude that while 'common sense' can be invoked, even potentially to supply a limitation missing from the prior art, it must still be supported by evidence and a reasoned explanation....[T]his is particularly true where the missing limitation goes to the heart of an invention." Arendi v. Apple, 832 F.3d at 1363.
MPEP § 2141
Short story: The Federal Circuit established the foundational rule that became the centerpiece of KSR: an obviousness rejection cannot be a bare conclusion. The examiner must articulate why a skilled person would have combined the references.
Rule: "Rejections on obviousness cannot be sustained by mere conclusory statements; instead, there must be some articulated reasoning with some rational underpinning to support the legal conclusion of obviousness."
Memory hook: "Kahn — no bare conclusions, articulate the reason."
MPEP § 2141 — In re Kahn, 441 F.3d 977, 988, 78 USPQ2d 1329, 1336 (Fed. Cir. 2006)
"The key to supporting any rejection under 35 U.S.C. 103 is the clear articulation of the reason(s) why the claimed invention would have been obvious. The Supreme Court in KSR noted that the analysis supporting a rejection under 35 U.S.C. 103 should be made explicit. The Court quoting In re Kahn, 441 F.3d 977, 988, 78 USPQ2d 1329, 1336 (Fed. Cir. 2006), stated that '[R]ejections on obviousness cannot be sustained by mere conclusory statements; instead, there must be some articulated reasoning with some rational underpinning to support the legal conclusion of obviousness.'" KSR, 550 U.S. at 418.
Every §103 rejection must cite at least one of these reasons to combine:
| # | Rationale | Memory Phrase |
|---|---|---|
| A | Combining prior art elements by known methods to yield predictable results | "Known + Known + Predictable = Obvious" |
| B | Simple substitution of one known element for another to obtain predictable results | "Swap one part for another" |
| C | Use of known technique to improve similar devices in the same way | "Known fix, same problem" |
| D | Applying known technique to a known device ready for improvement | "Upgrade a known device" |
| E | "Obvious to try" — finite number of identified, predictable solutions with reasonable expectation of success | "Pick from a short list" |
| F | Known work in one field prompts variations in another field (design incentives, market forces) | "Market forces drive it" |
| G | Teaching, suggestion, or motivation in the prior art | "Classic TSM" |
MPEP § 2141 — The Seven Rationales (from KSR, 550 U.S. at 415-21)
"Examples of rationales that may support a conclusion of obviousness include:
(A) Combining prior art elements according to known methods to yield predictable results; (B) Simple substitution of one known element for another to obtain predictable results; (C) Use of known technique to improve similar devices (methods, or products) in the same way; (D) Applying a known technique to a known device (method, or product) ready for improvement to yield predictable results; (E) 'Obvious to try' – choosing from a finite number of identified, predictable solutions, with a reasonable expectation of success; (F) Known work in one field of endeavor may prompt variations of it for use in either the same field or a different one based on design incentives or other market forces if the variations are predictable to one of ordinary skill in the art; (G) Some teaching, suggestion, or motivation in the prior art that would have led one of ordinary skill to modify the prior art reference or to combine prior art reference teachings to arrive at the claimed invention."
Note: "the list of rationales provided ... is not intended to be an all-inclusive list. Other rationales to support a conclusion of obviousness may be relied upon by Office personnel."
MPEP § 2141
Short story: A patent on computerized bank accounting was challenged. The Supreme Court held the invention obvious. The case is cited for the principle that "the mere existence of differences between the prior art and an invention does not establish the invention's non-obviousness." The gap between the prior art and the claimed invention must be large enough that a skilled person could not reasonably bridge it.
Rule: Differences alone don't prove non-obviousness. The gap must be "so great as to render the claim non-obvious to one reasonably skilled in the art."
Memory hook: "Dann — differences are necessary but not sufficient for non-obviousness."
MPEP § 2141 — Dann v. Johnston, 425 U.S. 219, 189 USPQ 257 (1976)
"Prior art is not limited just to the references being applied, but includes the understanding of one of ordinary skill in the art. The prior art reference (or references when combined) need not teach or suggest all the claim limitations. However, Office personnel must explain why the difference(s) between the prior art and the claimed invention would have been obvious to one of ordinary skill in the art. The 'mere existence of differences between the prior art and an invention does not establish the invention's nonobviousness.' Dann v. Johnston, 425 U.S. 219, 230, 189 USPQ 257, 261 (1976). The gap between the prior art and the claimed invention may not be 'so great as to render the [claim] nonobvious to one reasonably skilled in the art.' Id."
The Graham factors were applied in Dann v. Johnston — it is cited alongside Sakraida and Anderson's-Black Rock as one of the post-Graham Supreme Court decisions that used the Graham framework.
MPEP § 2141
Short story: These cases are cited to reinforce the four KSR errors (the problems with a rigid TSM approach). They confirm the Supreme Court's "expansive and flexible approach" to obviousness established in KSR.
Rule: Courts and examiners must apply an expansive and flexible approach to obviousness, not a formulaic TSM checklist.
Memory hook: "Novartis/West-Ward — post-KSR cases confirming the expansive, flexible approach."
MPEP § 2141 — Novartis Pharms. Corp. v. West-Ward Pharms. Int'l Ltd., 923 F.3d 1051, 1059 (Fed. Cir. 2019); Apple Inc. v. Samsung Elecs. Co., 839 F.3d 1034, 1047-48 (Fed. Cir. 2016); Aventis Pharma S.A. v. Hospira, Inc., 675 F.3d 1324, 1332 (Fed. Cir. 2012)
These cases are cited in MPEP § 2141 as authority for the four errors the Federal Circuit made in applying a rigid TSM test, as identified by the Supreme Court in KSR. See also In re Ethicon, Inc., 844 F.3d 1344, 1350 (Fed. Cir. 2017) (recalling that the Supreme Court has instructed decisionmakers to "apply 'an expansive and flexible approach' to obviousness") (quoting KSR, 550 U.S. at 415).
MPEP § 2141.01 | What can be used as prior art in a §103 rejection?
What the examiner is looking for: Before combining references to make an obviousness rejection, the examiner must confirm each reference qualifies as prior art under §102 for the application being examined. If a reference is removed as prior art (e.g., by a 1.130 affidavit), it also cannot be used for §103.
MPEP § 2141.01; § 2141.02
Short story: A patent dispute over cable tie mounts. The Federal Circuit stated that before you can use a reference in an obviousness analysis, you must first confirm it qualifies as prior art under §102. You can't skip the §102 analysis and jump straight to §103. (This case is also cited in § 2141.02 for the rule against reducing claims to their "gist.")
Rule: "Before answering Graham's 'content' inquiry, it must be known whether a patent or publication is in the prior art under 35 U.S.C. §102." A reference that is not prior art under §102 cannot support a §103 rejection.
Memory hook: "Panduit — §102 check comes before §103 combination."
MPEP § 2141.01 — Panduit Corp. v. Dennison Mfg. Co., 810 F.2d 1561, 1568, 1 USPQ2d 1593, 1597 (Fed. Cir.), cert. denied, 481 U.S. 1052 (1987)
"'Before answering Graham's "content" inquiry, it must be known whether a patent or publication is in the prior art under 35 U.S.C. § 102.' Panduit Corp. v. Dennison Mfg. Co., 810 F.2d 1561, 1568, 1 USPQ2d 1593, 1597 (Fed. Cir.), cert. denied, 481 U.S. 1052 (1987). Subject matter that is prior art under 35 U.S.C. 102 can be used to support a rejection under section 103."
MPEP § 2141.02 — (same case): "Panduit Corp. v. Dennison Mfg. Co., 810 F.2d 1561, 1 USPQ2d 1593 (Fed. Cir. 1987), cert. denied, 481 U.S. 1052 (1987) (district court improperly distilled claims down to a one word solution to a problem)."
MPEP § 2141.01
Short story: Dillon invented a fuel composition using tetra-orthoester compounds to reduce particulate emissions. The prior art showed similar compositions (tri-orthoesters) for a different purpose (dewatering). The court found that structural similarity can be enough for a prima facie case of obviousness even if the uses are different — the examiner does not need to show the prior art was used for the exact same purpose.
Rule: For a §103 rejection, it is not necessary that both structural similarity AND a suggestion of the same utility be shown. Structural similarity alone can create a prima facie case of obviousness; the applicant's newly discovered use is not required to be found in the prior art.
Memory hook: "Dillon — same structure, different purpose = still obvious prima facie."
MPEP § 2141.01 — In re Dillon, 919 F.2d 688, 693, 16 USPQ2d 1897, 1902 (Fed. Cir. 1990) (en banc)
Cited in MPEP § 2141 for the rule that: "[I]t is not necessary in order to establish a prima facie case of obviousness that both a structural similarity between a claimed and prior art compound (or a key component of a composition) be shown and that there be a suggestion in or expectation from the prior art that the claimed compound or composition will have the same or a similar utility as one newly discovered by applicant." In re Dillon, 919 F.2d at 693 (emphasis added).
"[T]he Court in KSR stated that '[t]he first error…in this case was…holding that courts and patent examiners should look only to the problem the patentee was trying to solve….' Federal Circuit case law prior to the Supreme Court's decision in KSR is generally in accord with these statements by the KSR Court. See e.g., In re Dillon, 919 F.2d 688, 693 (Fed. Cir. 1990) (en banc)."
MPEP § 2141.01
Short story: An inventor used sugar as an ingredient in a composition for a new purpose. The prior art disclosed using sugar in similar compositions for a different purpose. The court found this obvious, holding that the fact that the applicant uses sugar for a different purpose doesn't change the conclusion that its use in a prior art composition would have been obvious.
Rule: If a prior art reference discloses using a component (even for a different purpose), using that component in a similar composition is still obvious. Purpose of use does not equal patentability of structure.
Memory hook: "Lintner — different purpose for a known ingredient doesn't save you."
MPEP § 2141.01 — In re Lintner, 458 F.2d 1013, 1016, 173 USPQ 560, 562 (CCPA 1972)
"'The fact that appellant uses sugar for a different purpose does not alter the conclusion that its use in a prior art composition would be prima facie obvious from the purpose disclosed in the references.'" In re Lintner, 458 F.2d at 1016.
Cited in MPEP § 2141 alongside Dillon for the rule that the prior art's purpose of use need not match the applicant's purpose in order to establish a prima facie case of obviousness.
MPEP § 2141.01
Short story: These cases establish that admitted prior art — material the applicant itself acknowledges is in the prior art — can be used in both anticipation (§102) and obviousness (§103) rejections, regardless of whether it technically qualifies under a specific statutory category of §102.
Rule: Admitted prior art (what an applicant admits is known in the art) can be used for both §102 and §103 purposes, regardless of whether it technically qualifies as prior art under any specific provision of §102.
Memory hook: "Riverwood/Constant — if you admit it's prior art, the examiner can use it."
MPEP § 2141.01 — Riverwood Int'l Corp. v. R.A. Jones & Co., 324 F.3d 1346, 1354, 66 USPQ2d 1331, 1337 (Fed. Cir. 2003); Constant v. Advanced Micro-Devices Inc., 848 F.2d 1560, 1570, 7 USPQ2d 1057, 1063 (Fed. Cir. 1988)
"Furthermore, admitted prior art can be relied upon for both anticipation and obviousness determinations, regardless of whether the admitted prior art would otherwise qualify as prior art under the statutory categories of 35 U.S.C. 102. Riverwood Int'l Corp. v. R.A. Jones & Co., 324 F.3d 1346, 1354, 66 USPQ2d 1331, 1337 (Fed. Cir. 2003); Constant v. Advanced Micro-Devices Inc., 848 F.2d 1560, 1570, 7 USPQ2d 1057, 1063 (Fed. Cir. 1988). See MPEP § 2129 for discussion of admissions as prior art."
MPEP § 2141.01
Short story: These older CCPA and Board cases collectively confirm the basic rule that the "prior art" available for a §103 obviousness rejection is the same prior art defined by §102. No §102 qualification means no §103 use.
Rule: §103 uses §102 as the universe of available prior art. No §102 qualification = no §103 use.
Memory hook: "Wertheim/Hoeksema/Andresen — §103 borrows its prior art universe from §102."
MPEP § 2141.01 — In re Wertheim, 646 F.2d 527, 532, 209 USPQ 554, 560 (CCPA 1981); In re Hoeksema, 399 F.2d 269, 273, 158 USPQ 596, 600 (CCPA 1968); Ex parte Andresen, 212 USPQ 100, 102 (Bd. Pat. App. & Inter. 1981)
"Subject matter that is prior art under 35 U.S.C. 102 can be used to support a rejection under section 103. Ex parte Andresen, 212 USPQ 100, 102 (Bd. Pat. App. & Inter. 1981) ('it appears to us that the commentator [of 35 U.S.C.A.] and the [congressional] committee viewed section 103 as including all of the various bars to a patent as set forth in section 102.'). See also In re Wertheim, 646 F.2d 527, 532, 209 USPQ 554, 560 (CCPA 1981) ('Commensurate with the Senate Report and Mr. Federico's commentary, we have held that the term "prior art" refers "to at least the statutory prior art material named in § 102."'); and In re Hoeksema, 399 F.2d 269, 273, 158 USPQ 596, 600 (CCPA 1968) ('[w]hile 35 U.S.C. 102 is not directly involved in the issue on review, the conditions for patentability, novelty and loss of right to patent, there stated, may have relevance as to the disclosure which must be found in the prior art to find obviousness of an invention under section 103.')."
MPEP § 2141.01(a) | Is the reference from a relevant enough field to be used in a combination?
What the examiner is looking for: Even if a reference qualifies as prior art under §102, the examiner must show it is "analogous art" before using it in a §103 combination. A reference is analogous if it is either: (1) from the same field of endeavor as the claimed invention, OR (2) reasonably pertinent to the particular problem the inventor was trying to solve. Only ONE of these two tests needs to be met.
MPEP § 2141.01(a)
Short story: Bigio claimed a "hair brush" with a specific bristle configuration. The examiner used toothbrush patents as prior art. Bigio argued toothbrushes are completely different from hair brushes. The Federal Circuit disagreed: because "hair brush" can include brushes for any body hair (including facial hair), and toothbrushes are structurally similar small brushes that could be used on facial hair, the toothbrush references were from the same field of endeavor.
Rule: Two-part test for analogous art: (1) same field of endeavor (even if it addresses a different problem), OR (2) reasonably pertinent to the inventor's problem (even if not in the same field). Meet either one — the reference is analogous.
Memory hook: "Bigio Hair Brush — toothbrushes are analogous because both brush body hair. Two tests, only one needed."
MPEP § 2141.01(a) — In re Bigio, 381 F.3d 1320, 1325, 72 USPQ2d 1209, 1212 (Fed. Cir. 2004)
"In order for a reference to be proper for use in an obviousness rejection under 35 U.S.C. 103, the reference must be analogous art to the claimed invention. In re Bigio, 381 F.3d 1320, 1325, 72 USPQ2d 1209, 1212 (Fed. Cir. 2004). A reference is analogous art to the claimed invention if: (1) the reference is from the same field of endeavor as the claimed invention (even if it addresses a different problem); or (2) the reference is reasonably pertinent to the problem faced by the inventor (even if it is not in the same field of endeavor as the claimed invention). Note that 'same field of endeavor' and 'reasonably pertinent' are two separate tests for establishing analogous art; it is not necessary for a reference to fulfill both tests in order to qualify as analogous art. See Bigio, 381 F.3d at 1325."
"The patent application claimed a 'hair brush' having a specific bristle configuration. The Board affirmed the examiner's rejection of the claims as being obvious in view of prior art patents disclosing toothbrushes. The appellant disputed that the patent references constituted analogous art. On appeal, the court upheld the Board's interpretation of the claim term 'hair brush' to encompass any brush that may be used for any bodily hair, including facial hair. With this claim interpretation, the court applied the 'field of endeavor test' for analogous art and determined that the references were within the field of the inventor's endeavor and hence were analogous art because toothbrushes are structurally similar to small brushes for hair, and a toothbrush could be used to brush facial hair."
MPEP § 2141.01(a)
Short story: Firepass held a patent on using nitrogen-enriched air to reduce fire risk. Airbus challenged the patent, arguing that prior art in the oxygen depletion/hypoxic environment field was analogous. The Federal Circuit confirmed that the "same field of endeavor" test focuses on what the reference discloses, viewed from the perspective of the reality of the circumstances and the common sense of a skilled person.
Rule: When applying the "same field of endeavor" test, focus on what the reference actually discloses, not just the label on the field. Ask what a person of ordinary skill would reasonably consider the field to be.
Memory hook: "Airbus — field of endeavor is defined by what the reference discloses, not its title."
MPEP § 2141.01(a) — Airbus S.A.S. v. Firepass Corp., 941 F.3d 1374, 1380, 2019 USPQ2d 430083 (Fed. Cir. 2019)
"When determining whether the 'relevant field of endeavor' test is met, the examiner should consider 'explanations of the invention's subject matter in the patent application, including the embodiments, function, and structure of the claimed invention.' Airbus S.A.S. v. Firepass Corp., 941 F.3d 1374, 1380, 2019 USPQ2d 430083 (Fed. Cir. 2019) (quoting Bigio, 381 F.3d at 1325). When determining whether a prior art reference meets the 'same field of endeavor' test for the analogous art, the primary focus is on what the reference discloses. Airbus, 941 F.3d at 1380. The examiner must consider the disclosure of each reference 'in view of the "the reality of the circumstances."' Airbus, 941 F.3d at 1380 (quoting Bigio, 381 F.3d at 1326). These circumstances are to be weighed 'from the vantage point of the common sense likely to be exerted by one of ordinary skill in the art in assessing the scope of the endeavor.' Airbus, 941 F.3d at 1380."
MPEP § 2141.01(a)
Short story: ICON held a patent on a treadmill with a foldable incline feature. The examiner used a prior art reference about folding beds. ICON argued that bed references are not analogous to treadmill art. The court upheld the rejection, saying a reference is "reasonably pertinent" if a person of ordinary skill would logically have consulted it when trying to solve the inventor's problem.
Rule: For the "reasonably pertinent" test, ask: would a person of ordinary skill, when faced with the inventor's problem, have looked to this reference? If yes, it's analogous. The reference doesn't have to be from the exact same industry — just relevant to the same problem.
Memory hook: "ICON Treadmill/Folding Bed — if it solves the same kind of problem, it's analogous."
MPEP § 2141.01(a) — In re ICON Health and Fitness, Inc., 496 F.3d 1374, 1379-80 (Fed. Cir. 2007)
"As for the 'reasonably pertinent' test, the examiner should consider the problem faced by the inventor, as reflected - either explicitly or implicitly - in the specification. In order for a reference to be 'reasonably pertinent' to the problem, it must 'logically [] have commended itself to an inventor's attention in considering his problem.' In re ICON Health and Fitness, Inc., 496 F.3d 1374, 1379-80 (Fed. Cir. 2007) (quoting In re Clay, 966 F.2d 656, 658, 23 USPQ2d 1058, 1061 (Fed. Cir. 1992)). ... A reference outside of the field of endeavor is reasonably pertinent if a person of ordinary skill would have consulted it and applied its teachings when faced with the problem that the inventor was trying to solve. Airbus, 941 F.3d at 1380-82."
MPEP § 2141.01(a)
Short story: Clay invented a process for storing refined liquid hydrocarbon products by partially filling storage tanks with a gel. The examiner used a reference about filling petroleum reservoir space to keep oil in place. The Federal Circuit reversed, finding the reference was NOT analogous — the two fields (petroleum storage vs. refined products storage) faced different problems and a skilled person would not have been led to look at petroleum reservoir gelation when trying to solve the refined hydrocarbon storage problem.
Rule: A reference is only "reasonably pertinent" if it would logically have commended itself to the inventor's attention when considering the specific problem. Superficially similar technologies that address different problems are not necessarily analogous.
Memory hook: "Clay — NOT analogous. Petroleum reservoir ≠ refined storage; different problems, different fields."
MPEP § 2141.01(a) — In re Clay, 966 F.2d 656, 658, 23 USPQ2d 1058, 1061 (Fed. Cir. 1992)
Cited as the source for the "reasonably pertinent" test: a reference must "logically [] have commended itself to an inventor's attention in considering his problem." In re Clay, 966 F.2d at 658. Clay is the key counter-example — the petroleum reservoir reference was NOT analogous to the refined product storage invention because they addressed different problems. See also ICON Health and Fitness, Inc., 496 F.3d at 1379-80 (quoting Clay for the "reasonably pertinent" standard).
MPEP § 2141.01(a)
Short story: A dispute over trailer hitch lock design. The Federal Circuit confirmed that KSR directs courts to "construe the scope of analogous art broadly" because familiar items may have obvious uses beyond their primary purposes, and a skilled person can fit the teachings of multiple patents together "like pieces of a puzzle."
Rule: After KSR, analogous art should be construed broadly. Familiar items that can be used for purposes beyond their primary use should be considered potentially analogous.
Memory hook: "Wyers/Master Lock — KSR says cast a wide net for analogous art."
MPEP § 2141.01(a) — Wyers v. Master Lock Co., 616 F.3d 1231, 1238, 95 USPQ2d 1525, 1530 (Fed. Cir. 2010)
"The Federal Circuit reads KSR as 'direct[ing] us to construe the scope of analogous art broadly' because 'familiar items may have obvious uses beyond their primary purposes, and a person of ordinary skill often will be able to fit the teachings of multiple patents together like pieces of a puzzle.' Wyers v. Master Lock Co., 616 F.3d 1231, 1238, 95 USPQ2d 1525, 1530 (Fed. Cir. 2010) (quoting KSR, 550 U.S. at 402)."
MPEP § 2141.01(a)
Short story: Ellis's claims were about pedestrian floor gratings. The examiner combined structural grating references with shoe scraper references. Ellis argued these were non-analogous. The court disagreed: structural similarities and functional overlap between references carry far more weight than the PTO's classification scheme.
Rule: Whether two references are analogous depends much more on structural similarities and functional overlap between the inventions than on how the PTO has classified the patents.
Memory hook: "Ellis — function and structure matter more than PTO classification for analogous art."
MPEP § 2141.01(a) Section II — In re Ellis, 476 F.2d 1370, 1372, 177 USPQ 526, 527 (CCPA 1973)
"While Patent Office classification of references and the cross-references in the official search notes of the class definitions are some evidence of 'nonanalogy' or 'analogy' respectively, the court has found 'the similarities and differences in structure and function of the inventions disclosed in the references to carry far greater weight.' In re Ellis, 476 F.2d 1370, 1372, 177 USPQ 526, 527 (CCPA 1973) (The structural similarities and functional overlap between the structural gratings shown by one reference and the shoe scrapers of the type shown by another reference were readily apparent, and therefore the arts to which the reference patents belonged were reasonably pertinent to the art with which appellant's invention dealt (pedestrian floor gratings).)."
MPEP § 2141.01(a)
Short story: A simple mechanical invention was at issue. The court held that for simple mechanical devices, a broad spectrum of prior art must be explored, because it is reasonable to expect that similar problems arise across many areas where one of ordinary skill would be aware of them.
Rule: For simple mechanical inventions, the scope of analogous art is broad — any field in which a person of ordinary skill would recognize a similar problem.
Memory hook: "Stevenson — simple mechanics = wide analogous art net."
MPEP § 2141.01(a) Section IV — Stevenson v. Int'l Trade Comm., 612 F.2d 546, 550, 204 USPQ 276, 280 (CCPA 1979)
"'In a simple mechanical invention a broad spectrum of prior art must be explored and it is reasonable to permit inquiry into other areas where one of ordinary skill in the art would be aware that similar problems exist.' Stevenson v. Int'l Trade Comm., 612 F.2d 546, 550, 204 USPQ 276, 280 (CCPA 1979). See also In re Bigio, 381 F.3d 1320, 1325-26, 72 USPQ2d 1209, 1211-12 (Fed. Cir. 2004)."
MPEP § 2141.01(a)
Short story: Deminski's claims covered double-acting high-pressure gas transmission compressors with easily removable valves. The Board used prior art about piston pumps and compressors. On appeal, the court found these analogous because pumps and compressors have essentially the same function and structure when both are double-acting devices for moving fluid.
Rule: When different device types (pumps vs. compressors) have essentially the same function and structure, they are analogous to each other and prior art from either field can be applied.
Memory hook: "Deminski — pump and compressor both move fluid = analogous."
MPEP § 2141.01(a) Section IV — In re Deminski, 796 F.2d 436, 230 USPQ 313 (Fed. Cir. 1986)
"In re Deminski, 796 F.2d 436, 230 USPQ 313 (Fed. Cir. 1986) (Appellant's claims related to double-acting high pressure gas transmission line compressors in which the valves could be removed easily for replacement. The Board relied upon references which taught either a double-acting piston pump or a double-acting piston compressor. The court agreed that since the cited pumps and compressors have essentially the same function and structure, the field of endeavor includes both types of double-action piston devices for moving fluids.)."
MPEP § 2141.01(a)
Short story: Claims covered an instrument marker pen with a hinged holding means for easy attachment/removal. The patentee argued the fastener and hinge arts were non-analogous to the pen art. The court disagreed: because the inventor's problem was how to attach and detach things easily, looking at fastener and hinge art was exactly what a skilled person would do.
Rule: The relevant field is defined by the problem to be solved, not just the product category. If the inventor is solving a fastening problem, fastener art is analogous even if the product is a pen.
Memory hook: "Pentec Pen/Hinge — define the field by the problem, not the product."
MPEP § 2141.01(a) Section IV — Pentec, Inc. v. Graphic Controls Corp., 776 F.2d 309, 227 USPQ 766 (Fed. Cir. 1985)
"Pentec, Inc. v. Graphic Controls Corp., 776 F.2d 309, 227 USPQ 766 (Fed. Cir. 1985) (Claims at issue were directed to an instrument marker pen body, the improvement comprising a pen arm holding means having an integrally molded hinged member for folding over against the pen body. Although the patent owners argued the hinge and fastener art was nonanalogous, the court held that the problem confronting the inventor was the need for a simple holding means to enable frequent, secure attachment and easy removal of a marker pen to and from a pen arm, and one skilled in the pen art trying to solve that problem would have looked to the fastener and hinge art.)."
MPEP § 2141.01(a)
Short story: Goodyear's claims covered a braking material. The examiner used a reference from the clutch art. Goodyear argued clutch art was non-analogous to brake art. The Board disagreed: both brakes and clutches use interfacing materials to accomplish their purposes, so the friction problem is common to both.
Rule: References from related fields that share the same underlying technical problem (friction, in this case) are analogous to each other.
Memory hook: "Goodyear Brake/Clutch — same technical problem (friction) = analogous."
MPEP § 2141.01(a) Section IV — Ex parte Goodyear Tire & Rubber Co., 230 USPQ 357 (Bd. Pat. App. & Inter. 1985)
"Ex parte Goodyear Tire & Rubber Co., 230 USPQ 357 (Bd. Pat. App. & Inter. 1985) (A reference in the clutch art was held reasonably pertinent to the friction problem faced by the inventor, whose claims were directed to a braking material, because brakes and clutches utilize interfacing materials to accomplish their respective purposes.)."
MPEP § 2141.01(a)
Short story: A pacemaker patent included a "runaway inhibitor" to prevent the device from firing at dangerous rates. The prior art used high-power, high-frequency circuits to inhibit pulse runaway. The court found the high-power circuit references analogous to pacemakers because both face the same rate-limiting problem.
Rule: References from electrical arts outside the specific technology are analogous if they address the same functional problem — here, preventing runaway pulse rates.
Memory hook: "Medtronic — same rate-limiting problem makes high-power circuit art analogous to pacemakers."
MPEP § 2141.01(a) Section V — Medtronic, Inc. v. Cardiac Pacemakers, 721 F.2d 1563, 220 USPQ 97 (Fed. Cir. 1983)
"Medtronic, Inc. v. Cardiac Pacemakers, 721 F.2d 1563, 220 USPQ 97 (Fed. Cir. 1983) (Patent claims were drawn to a cardiac pacemaker which comprised, among other components, a runaway inhibitor means for preventing a pacemaker malfunction from causing pulses to be applied at too high a frequency. Two references disclosed circuits used in high power, high frequency devices which inhibited the runaway of pulses from a pulse source. The court held that one of ordinary skill in the pacemaker designer art faced with a rate-limiting problem would look to the solutions of others faced with rate limiting problems, and therefore the references were in an analogous art.)."
MPEP § 2141.01(a); § 2141.02
Short story: The patent involved PTFE (Teflon) tubing that prevented electrostatic buildup from fuel flow. The prior art references were in the rubber hose field, which faces the same electrostatic buildup problem. The court found the rubber hose art analogous to the PTFE tubing art because both are used by the same manufacturers for the same general problem. (This case also appears in § 2141.02 for the "as a whole" rule.)
Rule: When two different materials (PTFE and rubber) are used for the same application by the same industry and face the same problems, prior art addressing one is analogous to the other.
Memory hook: "Stratoflex PTFE/Rubber — same hose makers, same problem, analogous art."
MPEP § 2141.01(a) Section III — Stratoflex, Inc. v. Aeroquip Corp., 713 F.2d 1530, 218 USPQ 871 (Fed. Cir. 1983)
"Stratoflex, Inc. v. Aeroquip Corp., 713 F.2d 1530, 218 USPQ 871 (Fed. Cir. 1983) (Problem confronting inventor was preventing electrostatic buildup in PTFE tubing caused by hydrocarbon fuel flow while precluding leakage of fuel. Two prior art references relied upon were in the rubber hose art, both referencing the problem of electrostatic buildup caused by fuel flow. The court found that because PTFE and rubber are used by the same hose manufacturers and experience the same and similar problems, a solution found for a problem experienced with either PTFE or rubber hosing would be looked to when facing a problem with the other.)."
MPEP § 2141.02 — (same case for the "as a whole" rule): "In determining the differences between the prior art and the claims, the question under 35 U.S.C. 103 is not whether the differences themselves would have been obvious, but whether the claimed invention as a whole would have been obvious. Stratoflex, Inc. v. Aeroquip Corp., 713 F.2d 1530, 218 USPQ 871 (Fed. Cir. 1983)."
MPEP § 2141.01(a)
Short story: Claims covered a particulate composition (propionic acid absorbed onto vermiculite) as a food preservative. All the references involved absorbing biologically active materials onto various carriers. The Board found them all analogous because anyone in the preservative field would have been aware of the general carrier-absorption problem.
Rule: In chemical arts, references addressing the same general problem (absorption onto carriers for biological activity) are analogous even if the specific application differs.
Memory hook: "Bland — same underlying chemistry problem (absorption) = analogous across applications."
MPEP § 2141.01(a) Section III — Ex parte Bland, 3 USPQ2d 1103 (Bd. Pat. App. & Inter. 1986)
"Ex parte Bland, 3 USPQ2d 1103 (Bd. Pat App. & Inter. 1986) (Claims were drawn to a particulate composition useful as a preservative for an animal foodstuff (or a method of inhibiting fungus growth in an animal foodstuff therewith) comprising verxite having absorbed thereon propionic acid. All references were concerned with absorbing biologically active materials on carriers, and therefore the teachings in each of the various references would have been pertinent to the problems in the other references and the invention at hand.)."
MPEP § 2141.01(a)
Short story: Claims covered using dyes and developer materials for a dye penetrant inspection method. The examiner used references from the duplicating paper industry. The court found these analogous because the inventor's problem was one of dye chemistry, and a search for solutions in dye chemistry would naturally include all uses of dyes and developer materials.
Rule: When the underlying problem is in a specific science (dye chemistry), all prior art in that science is analogous, regardless of the end application.
Memory hook: "Mlot-Fijalkowski — define the problem by science (dye chemistry), not end product."
MPEP § 2141.01(a) Section III — In re Mlot-Fijalkowski, 676 F.2d 666, 213 USPQ 713 (CCPA 1982)
"In re Mlot-Fijalkowski, 676 F.2d 666, 213 USPQ 713 (CCPA 1982) (Problem faced by inventor was enhancement and immobilization of dye penetrant indications. References which taught the use of dyes and finely divided developer materials to produce colored images preferably in, but not limited to, the duplicating paper art were properly relied upon because the court found that inventor's problem was one of dye chemistry, and a search for its solution would include the dye arts in general.)."
MPEP § 2141.01(a)
Short story: A patent on pedalboard mounting systems for guitar effects pedals. Cited in the MPEP to confirm that when addressing whether a reference is analogous under the "reasonably pertinent" test, the problems addressed by both the reference and the claim must be identified and compared.
Rule: For the "reasonably pertinent" test, explicitly compare the problem addressed by the reference to the problem faced by the inventor. The two problems must be related.
Memory hook: "Donner — identify and compare the problems; both must be related for analogous art."
MPEP § 2141.01(a) — Donner Technology, LLC v. Pro Stage Gear, LLC, 979 F.3d 1353, 2020 USPQ2d 11335 (Fed. Cir. 2020)
"It may be necessary for the examiner to explain why an inventor seeking to solve the identified problem would have looked to the reference in an attempt to find a solution to the problem, i.e., factual reasons why the prior art is pertinent to the identified problem. See Donner Tech., LLC v. Pro Stage Gear, LLC, 979 F.3d 1353, 1359, 2020 USPQ2d 11335 (Fed. Cir. 2020) ('Thus, when addressing whether a reference is analogous art with respect to the claimed invention under a reasonable-pertinence theory, the problems to which both relate must be identified and compared.')."
MPEP § 2141.01(a)
Short story: These 2023 cases settled a question about multi-reference combinations: when combining two references for a §103 rejection, do those references need to be analogous to each other? The answer is no — each reference only needs to be analogous to the claimed invention.
Rule: In a multi-reference combination, each reference need only be analogous to the claimed invention, not to the other references in the combination.
Memory hook: "Sanofi/Corephotonics — references in a combo don't need to be analogous to each other, only to the claim."
MPEP § 2141.01(a) — Sanofi-Aventis Deutschland GMbH v. Mylan Pharms. Inc., 66 F.4th 1373, 1380, 2023 USPQ2d 552 (Fed. Cir. 2023); Corephotonics, Ltd. v. Apple Inc., 84 F.4th 990, 1007, 2023 USPQ2d 1202 (Fed. Cir. 2023)
"When more than one prior art reference is used as the basis of an obviousness rejection, it is not required that the references be analogous art to each other. See Sanofi-Aventis Deutschland GMbH v. Mylan Pharms. Inc., 66 F.4th 1373, 1380, 2023 USPQ2d 552 (Fed. Cir. 2023) and Corephotonics, Ltd. v. Apple Inc., 84 F.4th 990, 1007, 2023 USPQ2d 1202 (Fed. Cir. 2023)."
MPEP § 2141.01(a)
Short story: A streaming video technology patent dispute. The court clarified that the "field of endeavor" is not limited to the narrowest possible conception — it is not constrained to "the specific point of novelty, the narrowest possible conception of the field, or the particular focus within a given field."
Rule: The field of endeavor for purposes of the analogous art analysis is NOT limited to just the specific point of novelty or the narrowest slice of the field.
Memory hook: "Netflix — field of endeavor is NOT the narrowest slice. Think broader."
MPEP § 2141.01(a) — Netflix, Inc. v. DivX, LLC, 80 F.4th 1352, 1358-59, 2023 USPQ2d 1057 (Fed. Cir. 2023); Unwired Planet, LLC v. Google Inc., 841 F.3d 995, 1001, 120 USPQ2d 1593, 1597 (Fed. Cir. 2016)
"See also Donner Technology, LLC v. Pro Stage Gear, LLC, 979 F.3d 1353, 2020 USPQ2d 11335 (Fed. Cir. 2020); Sanofi-Aventis, 66 F.4th at 1378; and Netflix, Inc. v. DivX, LLC, 80 F.4th 1352, 1358-59, 2023 USPQ2d 1057 (Fed. Cir. 2023) ('The field of endeavor is "not limited to the specific point of novelty, the narrowest possible conception of the field, or the particular focus within a given field."') (quoting Unwired Planet, LLC v. Google Inc., 841 F.3d 995, 1001, 120 USPQ2d 1593, 1597 (Fed. Cir. 2016))."
MPEP § 2141.02 | The "as a whole" requirement — never compare piecemeal
What the examiner is looking for: The question under §103 is NOT "were the differences obvious?" — it is "was the claimed invention as a whole obvious?" Every limitation counts, including inherent properties disclosed in the specification. The examiner must not distill the claim down to its "gist" and compare only that gist to the prior art.
MPEP § 2141.02
Short story: Nortron's patent covered a vibration-testing machine where the support structure was a single, gapless, continuous piece (not bolted together). The prior art used a four-piece bolted structure. Schenck argued the invention is simply "making integral what had been made in pieces" — an obvious structural difference. The court reversed because the key insight was that the one-piece structure eliminated the need for dampening mechanisms, which was contrary to what the art expected. The inventive concept — the insight — is part of "the whole."
Rule: When an inventor discovers a new insight that runs counter to what the art expected, the invention should not be reduced to just its structural difference from the prior art. The inventive insight itself is part of "the subject matter as a whole."
Memory hook: "Schenck/Nortron — the insight (not just the structure) is part of the invention as a whole."
MPEP § 2141.02 — Schenck v. Nortron Corp., 713 F.2d 782, 218 USPQ 698 (Fed. Cir. 1983)
"In determining the differences between the prior art and the claims, the question under 35 U.S.C. 103 is not whether the differences themselves would have been obvious, but whether the claimed invention as a whole would have been obvious. Stratoflex, Inc. v. Aeroquip Corp., 713 F.2d 1530, 218 USPQ 871 (Fed. Cir. 1983); Schenck v. Nortron Corp., 713 F.2d 782, 218 USPQ 698 (Fed. Cir. 1983) (Claims were directed to a vibratory testing machine (a hard-bearing wheel balancer) comprising a holding structure, a base structure, and a supporting means which form 'a single integral and gaplessly continuous piece.' Nortron argued the invention is just making integral what had been made in four bolted pieces, improperly limiting the focus to a structural difference from the prior art and failing to consider the invention as a whole. The prior art perceived a need for mechanisms to dampen resonance, whereas the inventor eliminated the need for dampening via the one-piece gapless support structure. 'Because that insight was contrary to the understandings and expectations of the art, the structure effectuating it would not have been obvious to those skilled in the art.' 713 F.2d at 785, 218 USPQ at 700 (citations omitted).)."
MPEP § 2141.02
Short story: Hirao claimed a three-step process: steps 1 and 2 produced high-purity maltose (non-obvious), step 3 added it to food (obvious). The examiner argued step 3 was obvious and therefore the whole process was obvious. The court reversed: even if one step is obvious, if the overall combination is non-obvious (because steps 1-2 are non-obvious), the process as a whole is not obvious.
Rule: A multi-step claim must be evaluated as a whole. Even if one step is obvious, if the combination overall is non-obvious, the claim is non-obvious.
Memory hook: "Hirao — obvious step + non-obvious steps = non-obvious combination overall."
MPEP § 2141.02 — In re Hirao, 535 F.2d 67, 190 USPQ 15 (CCPA 1976)
"In re Hirao, 535 F.2d 67, 190 USPQ 15 (CCPA 1976) (Claims were directed to a three step process for preparing sweetened foods and drinks. The first two steps were directed to a process of producing high purity maltose (the sweetener), and the third was directed to adding the maltose to foods and drinks. The parties agreed that the first two steps were nonobvious but formed a known product and the third step was obvious. The Solicitor argued the preamble was directed to a process for preparing foods and drinks sweetened mildly and thus the specific method of making the high purity maltose (the first two steps in the claimed process) should not be given weight, analogizing with product-by-process claims. The court disagreed and held 'due to the admitted unobviousness of the first two steps of the claimed combination of steps, the subject matter as a whole would not have been obvious to one of ordinary skill in the art at the time the invention was made.' 535 F.2d at 69, 190 USPQ at 17 (emphasis in original). The preamble only recited the purpose of the process and did not limit the body of the claim. Therefore, the claimed process was a three-step process, not the product formed by two steps of the process or the third step of using that product.)."
MPEP §§ 2141.01; 2141.02
Short story: Gore held a patent on rapidly stretching unsintered, highly crystalline PTFE at a 10% per second rate to more than five times its length. The prior art: one reference taught rapid stretching of conventional polypropylene (low crystallinity) and another taught stretching unsintered PTFE slowly. The art specifically taught away from rapid stretching of crystalline PTFE. The trial court reduced the claim to its "gist" (10%/second stretching rate) and ignored other limitations. The Federal Circuit reversed.
Rule (§ 2141.02 — "Gist" Problem): Reducing a claim to its "gist" or "thrust" and ignoring other limitations violates the "as a whole" requirement.
Rule (§ 2141.02 — Teaching Away): When prior art specifically teaches away from a combination, that combination is not obvious even if both underlying references are analogous.
Memory hook: "Gore/Garlock — never reduce to 'gist'; and references that teach away defeat obviousness."
MPEP § 2141.02 Section II — W.L. Gore & Assoc., Inc. v. Garlock, Inc., 721 F.2d 1540, 220 USPQ 303 (Fed. Cir. 1983), cert. denied, 469 U.S. 851 (1984)
"Distilling an invention down to the 'gist' or 'thrust' of an invention disregards the requirement of analyzing the subject matter 'as a whole.' W.L. Gore & Assoc., Inc. v. Garlock, Inc., 721 F.2d 1540, 220 USPQ 303 (Fed. Cir. 1983), cert. denied, 469 U.S. 851 (1984) (restricting consideration of the claims to a 10% per second rate of stretching of unsintered PTFE and disregarding other limitations resulted in treating claims as though they read differently than allowed)."
MPEP § 2141.02 Section VI — (same case, teaching away): "A prior art reference must be considered in its entirety, i.e., as a whole, including portions that would lead away from the claimed invention. W.L. Gore & Assoc., Inc. v. Garlock, Inc., 721 F.2d 1540, 220 USPQ 303 (Fed. Cir. 1983), cert. denied, 469 U.S. 851 (1984) (Claims were directed to a process of producing a porous article by expanding shaped, unsintered, highly crystalline poly(tetrafluoroethylene) (PTFE) by stretching said PTFE at a 10% per second rate to more than five times the original length. The prior art teachings with regard to unsintered PTFE indicated the material does not respond to conventional plastics processing, and the material should be stretched slowly. A reference teaching rapid stretching of conventional plastic polypropylene with reduced crystallinity combined with a reference teaching stretching unsintered PTFE would not suggest rapid stretching of highly crystalline PTFE, in light of the disclosures in the art that teach away from the invention, i.e., that the conventional polypropylene should have reduced crystallinity before stretching, and that PTFE should be stretched slowly)."
MPEP § 2141.01 Section III — (same case, hindsight): "[I]t is difficult but necessary that the decisionmaker forget what he or she has been taught . . . about the claimed invention and cast the mind back to the time the invention was made (often as here many years), to occupy the mind of one skilled in the art. ..." W.L. Gore & Associates, Inc. v. Garlock, Inc., 721 F.2d 1540, 1553, 220 USPQ 303, 313 (Fed. Cir. 1983).
MPEP § 2141.02
Short story: A contact lens patent case. The district court reduced the claim to its "concept" — using a laser beam to create ridgeless depressions — and compared only that concept to the prior art, ignoring the specific material limitations (ophthalmic lens, cross-linked polymer, unsublimated polymer surface). The Federal Circuit reversed because the overlooked limitations mattered.
Rule: Distilling claims to a concept or "gist" and disregarding specific material, product, or method limitations violates the "as a whole" requirement. Every limitation must be considered.
Memory hook: "Bausch & Lomb — don't ignore the material/structural limitations when comparing to prior art."
MPEP § 2141.02 Section II — Bausch & Lomb v. Barnes-Hind/Hydrocurve, Inc., 796 F.2d 443, 447-49, 230 USPQ 416, 419-20 (Fed. Cir. 1986), cert. denied, 484 U.S. 823 (1987)
"Bausch & Lomb v. Barnes-Hind/Hydrocurve, Inc., 796 F.2d 443, 447-49, 230 USPQ 416, 419-20 (Fed. Cir. 1986), cert. denied, 484 U.S. 823 (1987) (District court focused on the 'concept of forming ridgeless depressions having smooth rounded edges using a laser beam to vaporize the material,' but 'disregarded express limitations that the product be an ophthalmic lens formed of a transparent cross-linked polymer and that the laser marks be surrounded by a smooth surface of unsublimated polymer.')."
MPEP § 2141.02
Short story: A patent dispute where one party argued the invention's advantage (rather than the full invention) should define the scope of comparison. The Federal Circuit stated that "treating the advantage as the invention disregards the statutory requirement that the invention be viewed 'as a whole.'"
Rule: The advantage or benefit of an invention is not "the invention." The invention is the full combination of elements as claimed.
Memory hook: "Jones v. Hardy — the benefit ≠ the invention. Compare the whole claim."
MPEP § 2141.02 Section II — Jones v. Hardy, 727 F.2d 1524, 1530, 220 USPQ 1021, 1026 (Fed. Cir. 1984)
"See also Jones v. Hardy, 727 F.2d 1524, 1530, 220 USPQ 1021, 1026 (Fed. Cir. 1984) ('treating the advantage as the invention disregards the statutory requirement that the invention be viewed "as a whole"')."
MPEP § 2141.02
Short story: Sponnoble invented a multi-compartment mixing vial. The key improvement was selecting butyl rubber with a silicone coating as the center seal plug, instead of natural rubber. The prior art knew there was a moisture leakage problem but misidentified the cause — blaming microscopic fissures in the glass rather than the plug material itself. Sponnoble discovered the actual cause (moisture transmitting through the rubber plug) and then selected the more impervious material. The court held the invention was non-obvious because the discovery of the source of the problem was itself part of the inventive concept.
Rule: A patentable invention can lie in the discovery of the source of a problem even if the solution is straightforward once the source is known. The discovery of the problem's source is part of "the subject matter as a whole."
Memory hook: "Sponnoble Vial — finding the cause of a problem is itself potentially inventive."
MPEP § 2141.02 Section III — In re Sponnoble, 405 F.2d 578, 585, 160 USPQ 237, 243 (CCPA 1969)
"'[A] patentable invention may lie in the discovery of the source of a problem even though the remedy may be obvious once the source of the problem is identified. This is part of the "subject matter as a whole" which should always be considered in determining the obviousness of an invention under 35 U.S.C. § 103.' In re Sponnoble, 405 F.2d 578, 585, 160 USPQ 237, 243 (CCPA 1969)."
"In In re Sponnoble, the claim was directed to a plural compartment mixing vial wherein a center seal plug was placed between two compartments for temporarily isolating a liquid-containing compartment from a solids-containing compartment. The claim differed from the prior art in the selection of butyl rubber with a silicone coating as the plug material instead of natural rubber. The prior art recognized that leakage from the liquid to the solids compartment was a problem, and considered the problem to be a result of moisture passing around the center plug because of microscopic fissures inherently present in molded or blown glass. The court found the inventor discovered the cause of moisture transmission was through the center plug, and there was no teaching in the prior art which would suggest the necessity of selecting applicant's plug material which was more impervious to liquids than the natural rubber plug of the prior art."
MPEP § 2141.02
Short story: Wiseman's claims covered carbon disc brakes with grooves to vent steam and prevent brake fade. Wiseman argued he discovered the problem (steam buildup) and its solution (grooves). The court affirmed obviousness: the prior art already showed grooves in disc brakes to reduce fading (for a different reason — cooling and dust removal). The solution was thus already in the prior art for a similar problem.
Rule: The "discovery of a problem's source makes it non-obvious" rule (Sponnoble) does NOT apply when the prior art already contains the same solution for a similar problem. If the solution was already there, discovering a new reason for the problem doesn't save the claim.
Memory hook: "Wiseman — Sponnoble doesn't work if the prior art already has your solution."
MPEP § 2141.02 Section III — In re Wiseman, 596 F.2d 1019, 1022, 201 USPQ 658, 661 (CCPA 1979)
"However, 'discovery of the cause of a problem . . does not always result in a patentable invention. . . . [A] different situation exists where the solution is obvious from prior art which contains the same solution for a similar problem.' In re Wiseman, 596 F.2d 1019, 1022, 201 USPQ 658, 661 (CCPA 1979) (emphasis in original)."
"In In re Wiseman, 596 F.2d at 1022, claims directed to grooved carbon disc brakes wherein the grooves were provided to vent steam or vapor during a braking action to minimize fading of the brakes were rejected as obvious over a reference showing carbon disc brakes without grooves in combination with a reference showing grooves in noncarbon disc brakes for the purpose of cooling the faces of the braking members and eliminating dust, thereby reducing fading of the brakes. The court affirmed the rejection, holding that even if the inventor discovered the cause of a problem, the solution would have been obvious from the prior art which contained the same solution (inserting grooves in disc brakes) for a similar problem."
MPEP § 2141.02
Short story: Antonie claimed a wastewater treatment device with a specific tank-volume-to-contactor-area ratio (0.12 gal/sq. ft.). This ratio had an inherent property: it maximized treatment capacity regardless of other variables. The prior art didn't recognize that this ratio was a result-effective variable. The court held the invention was non-obvious because the inherent property of the claimed ratio — the key technical insight — was not recognized in the prior art.
Rule: When evaluating the claimed invention "as a whole," you must include not just what is literally recited in the claim but also inherent properties that are disclosed in the specification. If the prior art did not recognize the inherent property, that property is part of the inventive concept.
Memory hook: "Antonie — disclosed inherent properties count as part of the whole invention."
MPEP § 2141.02 Section V — In re Antonie, 559 F.2d 618, 620, 195 USPQ 6, 8 (CCPA 1977)
"'In determining whether the invention as a whole would have been obvious under 35 U.S.C. 103, we must first delineate the invention as a whole. In delineating the invention as a whole, we look not only to the subject matter which is literally recited in the claim in question... but also to those properties of the subject matter which are inherent in the subject matter and are disclosed in the specification. . . Just as we look to a chemical and its properties when we examine the obviousness of a composition of matter claim, it is this invention as a whole, and not some part of it, which must be obvious under 35 U.S.C. 103.' In re Antonie, 559 F.2d 618, 620, 195 USPQ 6, 8 (CCPA 1977) (emphasis in original) (citations omitted) (The claimed wastewater treatment device had a tank volume to contactor area of 0.12 gal./sq. ft. The court found the invention as a whole was the ratio of 0.12 and its inherent property that the claimed devices maximized treatment capacity regardless of other variables in the devices. The prior art did not recognize that treatment capacity was a function of the tank volume to contactor ratio, and therefore the parameter optimized was not recognized in the art to be a result-effective variable.)."
MPEP § 2141.02
Short story: Papesch claimed a chemical compound. The examiner argued that structurally similar compounds were known. Papesch showed his compound had different properties (it was an anti-inflammatory agent). The court held that "from the standpoint of patent law, a compound and all its properties are inseparable."
Rule: A chemical compound and ALL of its properties are inseparable for purposes of §103. You cannot evaluate a compound for obviousness without considering its properties.
Memory hook: "Papesch — compound + all properties = the whole invention."
MPEP § 2141.02 Section V — In re Papesch, 315 F.2d 381, 391, 137 USPQ 43, 51 (CCPA 1963)
"Note, however, that after KSR, the presence of a known result-effective variable would be one, but not necessarily the only, motivation for a person of ordinary skill in the art to experiment to reach another workable product or process. See MPEP § 2144.05, subsection II.B. See also In re Papesch, 315 F.2d 381, 391, 137 USPQ 43, 51 (CCPA 1963) ('From the standpoint of patent law, a compound and all its properties are inseparable.')."
MPEP § 2141.02
Short story: The Federal Circuit clarified that obviousness cannot be based on an inherent property that was not known at the relevant time. If the prior art did not inherently have the property AND that property wasn't recognized, it cannot make the claim obvious.
Rule: Obviousness cannot be predicated on what was not known at the relevant time, even if the inherency of a certain feature is later established.
Memory hook: "Rijckaert — unknown inherency at the time = can't support obviousness."
MPEP § 2141.02 Section V — In re Rijckaert, 9 F.3d 1531, 28 USPQ2d 1955 (Fed. Cir. 1993)
"Obviousness cannot be predicated on what is not known at the relevant time, even if the inherency of a certain feature is later established. See In re Rijckaert, 9 F.3d 1531, 28 USPQ2d 1955 (Fed. Cir. 1993). See MPEP § 2112 for the requirements of rejections based on inherency."
MPEP § 2141.02
Short story: Fulton argued that because the prior art disclosed multiple alternatives, it "taught away" from the claimed combination. The court rejected this argument: the mere disclosure of more than one alternative does not constitute "teaching away" — teaching away requires that the reference criticize, discredit, or otherwise discourage the claimed solution.
Rule: A prior art reference that discloses multiple alternatives does NOT teach away from any of them just by mentioning them. "Teaching away" requires active criticism, discrediting, or discouragement of the claimed approach.
Memory hook: "Fulton — mentioning alternatives is not teaching away. You need active discouragement."
MPEP § 2141.02 Section VI — In re Fulton, 391 F.3d 1195, 1201, 73 USPQ2d 1141, 1146 (Fed. Cir. 2004)
"However, 'the prior art's mere disclosure of more than one alternative does not constitute a teaching away from any of these alternatives because such disclosure does not criticize, discredit, or otherwise discourage the solution claimed….' In re Fulton, 391 F.3d 1195, 1201, 73 USPQ2d 1141, 1146 (Fed. Cir. 2004). See also MPEP § 2123."
MPEP § 2141.02
Short story: A patent on industrial attachment tools. The patentee argued that a modification would impede a desirable function of the prior art reference, so there was no motivation to combine. The court held that even when a modification has simultaneous advantages and disadvantages, that does not automatically defeat motivation to combine.
Rule: The fact that a proposed combination has simultaneous advantages and disadvantages does not necessarily mean there is no motivation to combine. Trade-offs alone do not defeat an obviousness rejection.
Memory hook: "Allied — simultaneous pros and cons don't automatically kill motivation to combine."
MPEP § 2141.02 Section VI — Allied Erecting v. Genesis Attachments, 825 F.3d 1373, 1381, 119 USPQ2d 1132, 1138 (Fed. Cir. 2016)
"Allied Erecting v. Genesis Attachments, 825 F.3d 1373, 1381, 119 USPQ2d 1132, 1138 (Fed. Cir. 2016) ('Although modification of the movable blades may impede the quick change functionality disclosed by Caterpillar, "[a] given course of action often has simultaneous advantages and disadvantages, and this does not necessarily obviate motivation to combine."' (quoting Medichem, S.A. v. Rolabo, S.L., 437 F.3d 1157, 1165, 77 USPQ2d 1865, 1870 (Fed Cir. 2006) (citation omitted)))."
MPEP § 2141.03 | Who is this hypothetical person, and why does it matter?
What the examiner is looking for: The entire §103 analysis is conducted through the eyes of a "person of ordinary skill in the art" (POSITA). The examiner must either explicitly state the level of skill or implicitly indicate it through the prior art applied. The POSITA is a hypothetical person — not an expert, not a novice, not the inventor.
MPEP § 2141.03
Short story: GPAC involved determining who "a person of ordinary skill in the art" was for a fiberglass manufacturing process. The Federal Circuit articulated five factors that courts and examiners should consider when defining the level of ordinary skill.
The Five GPAC Factors:
Rule: Use these five factors to define the hypothetical POSITA. Not all factors will be present in every case; one or more may predominate.
Memory hook: "GPAC Five: Problems, Solutions, Innovation Rate, Sophistication, Education."
MPEP § 2141.03 — In re GPAC, Inc., 57 F.3d 1573, 1579, 35 USPQ2d 1116, 1121 (Fed. Cir. 1995)
"Factors that may be considered in determining the level of ordinary skill in the art may include: (A) 'type of problems encountered in the art;' (B) 'prior art solutions to those problems;' (C) 'rapidity with which innovations are made;' (D) 'sophistication of the technology; and' (E) 'educational level of active workers in the field. In a given case, every factor may not be present, and one or more factors may predominate.' In re GPAC, 57 F.3d 1573, 1579, 35 USPQ2d 1116, 1121 (Fed. Cir. 1995); Custom Accessories, Inc. v. Jeffrey-Allan Indus., Inc., 807 F.2d 955, 962, 1 USPQ2d 1196, 1201 (Fed. Cir. 1986); Environmental Designs, Ltd. V. Union Oil Co., 713 F.2d 693, 696, 218 USPQ 865, 868 (Fed. Cir. 1983)."
MPEP § 2141.03
Short story: (Same case, second appearance.) The Supreme Court emphasized that a POSITA is not an automaton. A person of ordinary skill "will be able to fit the teachings of multiple patents together like pieces of a puzzle" and will employ "inferences and creative steps."
Rule: The POSITA is a person of ordinary creativity, not an automaton. They can recognize that multiple patents can be combined creatively, even without explicit instruction to do so.
Memory hook: "KSR POSITA — creative human being, not a robot."
MPEP § 2141.03 — KSR Int'l Co. v. Teleflex Inc., 550 U.S. 398, 421, 82 USPQ2d 1385, 1397 (2007)
"'A person of ordinary skill in the art is also a person of ordinary creativity, not an automaton.' KSR Int'l Co. v. Teleflex Inc., 550 U.S. 398, 421, 82 USPQ2d 1385, 1397 (2007). '[I]n many cases a person of ordinary skill will be able to fit the teachings of multiple patents together like pieces of a puzzle.' Id. at 420. Office personnel may also take into account 'the inferences and creative steps that a person of ordinary skill in the art would employ.' Id. at 418."
MPEP § 2141.03
Short story: A patent on a natural gas processing system. The court stated that the examiner must ascertain what would have been obvious to "one of ordinary skill," not to the inventor, a judge, a layman, those in remote arts, or geniuses in the art.
Rule: The POSITA is an ordinary skilled worker — not the inventor, not an expert, not a layman. The analysis must be from the perspective of a typical person working in the field.
Memory hook: "Environmental Designs — POSITA is ordinary, not the inventor, not a genius, not a layman."
MPEP § 2141.03 Section III — Environmental Designs, Ltd. v. Union Oil Co., 713 F.2d 693, 218 USPQ 865 (Fed. Cir. 1983), cert. denied, 464 U.S. 1043 (1984)
"'The importance of resolving the level of ordinary skill in the art lies in the necessity of maintaining objectivity in the obviousness inquiry.' Ryko Mfg. Co. v. Nu-Star, Inc., 950 F.2d 714, 718, 21 USPQ2d 1053, 1057 (Fed. Cir. 1991). The examiner must ascertain what would have been obvious as of the relevant time to one of ordinary skill in the art, and not to the inventor, a judge, a layman, those skilled in remote arts, or to geniuses in the art at hand. Environmental Designs, Ltd. v. Union Oil Co., 713 F.2d 693, 218 USPQ 865 (Fed. Cir. 1983), cert. denied, 464 U.S. 1043 (1984)."
MPEP § 2141.03
Short story: The examiner defined "one of ordinary skill" as a doctorate-level engineer or scientist working at least 40 hours per week in semiconductor research. The Board found this too high. The POSITA is not definable by credentials — it is defined by the ability to understand the scientific and engineering principles applicable to the art.
Rule: The POSITA cannot be defined simply by academic credentials or hours worked. The test is whether the person can understand and apply the scientific and engineering principles in the relevant field.
Memory hook: "Hiyamizu — POSITA is defined by knowledge of the art, not by a diploma."
MPEP § 2141.03 — Ex parte Hiyamizu, 10 USPQ2d 1393, 1394 (Bd. Pat. App. & Inter. 1988)
"The 'hypothetical "person having ordinary skill in the art" to which the claimed subject matter pertains would, of necessity have the capability of understanding the scientific and engineering principles applicable to the pertinent art.' Ex parte Hiyamizu, 10 USPQ2d 1393, 1394 (Bd. Pat. App. & Inter. 1988) (The Board disagreed with the examiner's definition of one of ordinary skill in the art (a doctorate level engineer or scientist working at least 40 hours per week in semiconductor research or development), finding that the hypothetical person is not definable by way of credentials, and that the evidence in the application did not support the conclusion that such a person would require a doctorate or equivalent knowledge in science or engineering.)."
MPEP § 2141.03
Short story: Merck argued that a reference was not prior art, but it was used to demonstrate the level of skill in the art at the time of invention. The Federal Circuit confirmed that references that are not themselves prior art may still be used as evidence of the level of ordinary skill in the art at the relevant time.
Rule: References that do not qualify as prior art under §102 can still be used to show the level of ordinary skill in the art at or around the time of the invention.
Memory hook: "Merck — non-prior art can show the level of skill (even if it can't be used for obviousness)."
MPEP § 2141.03 — In re Merck & Co., Inc., 800 F.2d 1091, 1098, 231 USPQ 375, 380 (Fed. Cir. 1986)
"References which are not prior art may be relied upon to demonstrate the level of ordinary skill in the art at or around the relevant time. See In re Merck & Co., Inc., 800 F.2d 1091, 1098, 231 USPQ 375, 380 (Fed. Cir. 1986) ('Evidence of contemporaneous invention is probative of "the level of knowledge in the art at the time the invention was made."' (citing In re Farrenkopf, 713 F.2d 714, 720, 219 USPQ 1, 6 (Fed. Cir. 1983)))."
MPEP § 2141.03
Short story: A water treatment technology patent. The court cited the "fact of near-simultaneous invention" as strong evidence of the level of ordinary skill: if two people independently developed the same thing around the same time, it shows what a person of ordinary skill could achieve.
Rule: Near-simultaneous invention by independent parties is strong evidence of the level of ordinary skill in the art (though not automatically determinative of obviousness).
Memory hook: "Ecolochem — simultaneous independent invention tells you what POSITA could do."
MPEP § 2141.03 — Ecolochem, Inc. v. S. California Edison Co., 227 F.3d 1361, 1379, 56 USPQ2d 1065, 1079 (Fed. Cir. 2000)
"Ecolochem, Inc. v. S. California Edison Co., 227 F.3d 1361, 1379, 56 USPQ2d 1065, 1079 (Fed. Cir. 2000) ('The fact of near-simultaneous invention, though not determinative of statutory obviousness, is strong evidence of what constitutes the level of ordinary skill in the art.' (quoting The Int'l Glass Co. v. United States, 408 F.2d 395, 405, 159 USPQ 434, 442 (Ct. Cl. 1969)))."
MPEP § 2141.03
Short story: These cases establish that non-prior-art materials (like unpublished internal company documents and engineering drawings) can be used not as prior art references, but to show (1) the level of ordinary skill in the art and (2) that motivation to combine was implicit in the knowledge of a POSITA.
Rule: Non-prior-art evidence (including unpublished drawings or internal documents) may be used to show motivation to combine that is implicit in the knowledge of a POSITA, and to demonstrate the level of ordinary skill.
Memory hook: "Thomas & Betts / Nat'l Steel Car — internal docs can show motivation and skill level, even if not prior art."
MPEP § 2141.03 — Thomas & Betts Corp. v. Litton Sys., Inc., 720 F.2d 1572, 1580-81, 220 USPQ 1, 7 (Fed. Cir. 1983); Nat'l Steel Car, Ltd. v. Can. Pac. Ry., Ltd., 357 F.3d 1319, 1337-38, 69 USPQ2d 1641, 1656 (Fed. Cir. 2004)
"See also Thomas & Betts Corp. v. Litton Sys., Inc., 720 F.2d 1572, 1580-81, 220 USPQ 1, 7 (Fed. Cir. 1983) ('Thus, the [unpublished internal materials], though not technically prior art, were, in effect, properly used as indicators of the level of ordinary skill in the art to which the invention pertained.')."
"Moreover, references not available as prior art may be relevant to establishing 'a motivation to combine which is implicit in the knowledge of one of ordinary skill in the art.' Nat'l Steel Car, Ltd. v. Can. Pac. Ry., Ltd., 357 F.3d 1319, 1337-38, 69 USPQ2d 1641, 1656 (Fed. Cir. 2004) (holding that a drawing made by an engineer that was not prior art can, nonetheless, '... be used to demonstrate a motivation to combine implicit in the knowledge of one of ordinary skill in the art.')."
MPEP § 2141.03
Short story: These cases confirm that patent examiners themselves are "persons of scientific competence" in their fields. Their findings about what a POSITA would understand from prior art references are informed by their scientific background and experience. Examiners are presumed to know the level of skill in the art.
Rule: Patent examiners are presumed to have expertise in interpreting prior art references and to be familiar with the level of skill in the art from their work. Their fact-findings about what the prior art means to a POSITA are informed by their scientific background.
Memory hook: "Berg/PowerOasis — examiners are presumed to be POSITA-level experts in their field."
MPEP § 2141.03 — In re Berg, 320 F.3d 1310, 1315, 65 USPQ2d 2003, 2007 (Fed. Cir. 2003); PowerOasis, Inc. v. T-Mobile USA, Inc., 522 F.3d 1299, 86 USPQ2d 1385 (Fed. Cir. 2008)
"In addition to the factors above, Office personnel may rely on their own technical expertise to describe the knowledge and skills of a person of ordinary skill in the art. The Federal Circuit has stated that examiners and administrative patent judges on the Board are 'persons of scientific competence in the fields in which they work' and that their findings are 'informed by their scientific knowledge, as to the meaning of prior art references to persons of ordinary skill in the art.' In re Berg, 320 F.3d 1310, 1315, 65 USPQ2d 2003, 2007 (Fed. Cir. 2003). In addition, examiners 'are assumed to have some expertise in interpreting the references and to be familiar from their work with the level of skill in the art.' PowerOasis, Inc. v. T-Mobile USA, Inc., 522 F.3d 1299, 86 USPQ2d 1385 (Fed. Cir. 2008) (quoting Am. Hoist & Derrick Co. v. Sowa & Sons, 725 F.2d 1350, 1360, 220 USPQ 763, 770 (Fed. Cir. 1984))."
MPEP § 2141.03
Short story: A patent on a ride-sharing location-sharing system was challenged. The specification was entirely silent on how to transmit user locations from a server to a mobile device. The court found this silence itself indicated that the implementation was within ordinary skill — something a skilled person would know how to do without explicit instruction.
Rule: When a specification is silent on how to accomplish a particular step or function, that silence may indicate the implementation is within ordinary skill. The specification itself can be evidence of the level of ordinary skill.
Memory hook: "Uber/X One — silence in the spec about a technical detail = it's within ordinary skill."
MPEP § 2141.03 — Uber Techs., Inc. v. X One, Inc., 957 F.3d 1334, 1339, 2020 USPQ2d 10476 (Fed. Cir. 2020)
"The level of disclosure in the specification of the application under examination or in relevant references may also be informative of the knowledge and skills of a person of ordinary skill in the art. For example, if the specification is entirely silent on how a certain step or function is achieved, that silence may suggest that figuring out how to achieve that step or function is within the ordinary skill in the art, provided that the specification complies with 35 U.S.C. 112. Uber Techs., Inc. v. X One, Inc., 957 F.3d 1334, 1339, 2020 USPQ2d 10476 (Fed. Cir. 2020) ('The specification of the '593 patent is entirely silent on how to transmit user locations and maps from a server to a user's mobile device, suggesting that a person of ordinary skill in the art was more than capable of selecting between the known methods of accomplishing this. The '593 patent confirms that its invention, including any necessary plotting, "utilizes existing platforms and infrastructure" and does not "require development of new cell phone or PDA technology, nor do[es it] require development of new cellular communication infrastructure."')."
MPEP § 2141.03
Short story: A patent dispute where no specific finding of ordinary skill level was made. The Federal Circuit held that when the only evidence of the level of skill is the prior art itself, the invention can be held obvious without a separate explicit finding of the skill level, since the prior art itself reflects an appropriate level.
Rule: When the prior art of record reflects the level of ordinary skill, a separate explicit finding of a particular skill level is not required. The prior art speaks for itself.
Memory hook: "Chore-Time — the prior art can implicitly define the level of skill; no separate finding needed."
MPEP § 2141.03 Section II — Chore-Time Equipment, Inc. v. Cumberland Corp., 713 F.2d 774, 218 USPQ 673 (Fed. Cir. 1983)
"If the only facts of record pertaining to the level of skill in the art are found within the prior art of record, the court has held that an invention may be held to have been obvious without a specific finding of a particular level of skill where the prior art itself reflects an appropriate level. Chore-Time Equipment, Inc. v. Cumberland Corp., 713 F.2d 774, 218 USPQ 673 (Fed. Cir. 1983). See also Okajima v. Bourdeau, 261 F.3d 1350, 1355, 59 USPQ2d 1795, 1797 (Fed. Cir. 2001)."
MPEP § 2141.03
Short story: A car wash equipment patent case. The Federal Circuit emphasized that resolving the level of ordinary skill is crucial because it determines the standard for objectivity: the analysis must reflect what that hypothetical skilled person would have known, not the inventor, a judge, or a layman.
Rule: The importance of defining the level of ordinary skill is that it preserves objectivity. The §103 analysis must be conducted from the specific perspective of the POSITA — not from the inventor's knowledge, and not from hindsight using the patent itself as a guide.
Memory hook: "Ryko — level of skill = the objectivity anchor. Get it wrong and you get hindsight."
MPEP § 2141.03 Section III — Ryko Mfg. Co. v. Nu-Star, Inc., 950 F.2d 714, 718, 21 USPQ2d 1053, 1057 (Fed. Cir. 1991)
"'The importance of resolving the level of ordinary skill in the art lies in the necessity of maintaining objectivity in the obviousness inquiry.' Ryko Mfg. Co. v. Nu-Star, Inc., 950 F.2d 714, 718, 21 USPQ2d 1053, 1057 (Fed. Cir. 1991). The examiner must ascertain what would have been obvious as of the relevant time to one of ordinary skill in the art, and not to the inventor, a judge, a layman, those skilled in remote arts, or to geniuses in the art at hand. Environmental Designs, Ltd. v. Union Oil Co., 713 F.2d 693, 218 USPQ 865 (Fed. Cir. 1983), cert. denied, 464 U.S. 1043 (1984)."
| Case | Key Point | MPEP § |
|---|---|---|
| Graham v. John Deere | Four-factor test for all §103 analysis | 2141 |
| KSR v. Teleflex | Flexible approach; predictable combos obvious; 4 errors of rigid TSM | 2141 |
| U.S. v. Adams | Known parts + unexpected result/teaching away = non-obvious | 2141 |
| Anderson's-Black Rock | Each element does same job = obvious | 2141 |
| Sakraida | Old parts, same functions, new arrangement = obvious | 2141 |
| Perfect Web | Common sense needs a reasoned explanation, not bare assertion | 2141 |
| Arendi v. Apple | Common sense especially needs evidence when missing element is central | 2141 |
| In re Kahn | No bare conclusions; must articulate reasoning | 2141 |
| Dann v. Johnston | Differences alone don't prove non-obviousness | 2141 |
| Panduit v. Dennison | §102 check before §103; no distilling to gist | 2141.01 / 2141.02 |
| In re Dillon | Structural similarity → prima facie obvious even if different purpose | 2141.01 |
| In re Lintner | Known ingredient used for different purpose still obvious | 2141.01 |
| Riverwood / Constant | Admitted prior art usable for §102 and §103 regardless of §102 category | 2141.01 |
| In re Bigio | Two-part analogous art test; either test satisfied is enough | 2141.01(a) |
| Airbus v. Firepass | Field of endeavor = what reference discloses, from skilled person's view | 2141.01(a) |
| ICON Health & Fitness | Reasonably pertinent = would POSITA consult it for the same problem? | 2141.01(a) |
| In re Clay | Different problems = not analogous (petroleum reservoir ≠ refined storage) | 2141.01(a) |
| Wyers v. Master Lock | Post-KSR: construe analogous art broadly | 2141.01(a) |
| In re Ellis | Function/structure > PTO classification for analogous art | 2141.01(a) |
| Stevenson v. ITC | Simple mechanical = broad analogous art | 2141.01(a) |
| In re Deminski | Same function (pump = compressor) = analogous | 2141.01(a) |
| Pentec v. Graphic Controls | Define field by problem to be solved | 2141.01(a) |
| Ex parte Goodyear | Same technical problem (friction) = analogous | 2141.01(a) |
| Medtronic v. Cardiac Pacemakers | Same functional problem (rate limiting) = analogous | 2141.01(a) |
| Stratoflex v. Aeroquip | Same industry/problem = analogous; compare whole invention | 2141.01(a) / 2141.02 |
| In re Mlot-Fijalkowski | Define field by underlying science, not end product | 2141.01(a) |
| Donner Technology | Identify and compare problems for reasonably pertinent test | 2141.01(a) |
| Sanofi / Corephotonics | References in combo need not be analogous to each other | 2141.01(a) |
| Netflix v. DivX | Field of endeavor ≠ narrowest slice of the field | 2141.01(a) |
| Schenck v. Nortron | Inventive insight is part of "the whole" | 2141.02 |
| In re Hirao | Non-obvious step + obvious step = non-obvious whole | 2141.02 |
| W.L. Gore v. Garlock | No gist reductions; teaching away defeats obviousness | 2141.02 |
| Bausch & Lomb | Never ignore specific material/structural limitations | 2141.02 |
| Jones v. Hardy | Benefit ≠ the invention | 2141.02 |
| In re Sponnoble | Discovering the source of a problem = patentable insight | 2141.02 |
| In re Wiseman | Sponnoble rule fails if prior art already had the solution | 2141.02 |
| In re Antonie | Disclosed inherent properties = part of the whole invention | 2141.02 |
| In re Papesch | Chemical compound + all properties = inseparable whole | 2141.02 |
| In re Rijckaert | Unknown inherency at the time ≠ basis for obviousness | 2141.02 |
| In re Fulton | Disclosing alternatives ≠ teaching away | 2141.02 |
| Allied Erecting | Trade-offs don't automatically kill motivation to combine | 2141.02 |
| In re GPAC | Five factors define POSITA | 2141.03 |
| KSR — POSITA | POSITA is creative, not an automaton | 2141.03 |
| Environmental Designs | POSITA = ordinary worker, not inventor/genius/layman | 2141.03 |
| Ex parte Hiyamizu | POSITA defined by knowledge, not credentials | 2141.03 |
| In re Merck | Non-prior-art refs can show level of skill | 2141.03 |
| Ecolochem | Simultaneous invention = evidence of skill level | 2141.03 |
| Thomas & Betts / Nat'l Steel Car | Non-prior-art docs can show implicit motivation to combine | 2141.03 |
| In re Berg / PowerOasis | Examiners presumed to have POSITA-level expertise | 2141.03 |
| Chore-Time | Prior art implicitly defines skill level; no separate finding needed | 2141.03 |
| Ryko Mfg. | Level of skill = objectivity anchor against hindsight | 2141.03 |
| Uber v. X One | Spec silence on implementation = within ordinary skill | 2141.03 |