§ 103 Obviousness
Motivation to Combine
Why a person of ordinary skill would combine prior art references — the heart of every § 103 obviousness analysis after KSR.
KSR International Co. v. Teleflex Inc. (S.Ct. 2007)
KSR rejected the rigid TSM (teaching, suggestion, motivation) test. The obviousness inquiry must be flexible — any reason a skilled artisan would combine references suffices. Combining known elements using known methods to yield predictable results is likely obvious.
Five KSR Rationales
Recognized Reasons to Combine Prior Art References
The USPTO's KSR Guidelines (2007) and subsequent Federal Circuit decisions recognize these five rationales — any one is sufficient to establish a motivation to combine:
Combining Prior Art Elements
Combining known elements using known methods yields predictable results.
Combining a known GPS receiver with a known speed sensor to build a navigation system — both elements perform the same functions they did separately.
Test
Each element performs same function it did before combination; result is predictable
Simple Substitution
Substituting one known element for another to obtain predictable results.
Replacing a magnetic hard drive with a flash memory storage device in a known portable device architecture — different technology, same function.
Test
Known alternative elements exist; substitution yields expected (not surprising) result
Use of Known Technique
Applying a known technique to a known device ready for improvement.
Applying a known compression algorithm (already used in audio) to video data — technique is known, application domain slightly different.
Test
Technique is already known in the art; applying it to this context was recognized as reasonable improvement
Obvious to Try
Choosing from a finite number of identified, predictable solutions.
If only 3 known catalyst materials exist for a reaction, trying each one to optimize yield is obvious to try.
Test
FINITE options; all identified in prior art; POSITA has reason to try each; no unexpected result
Design Incentives / Market Forces
Prior art from one field applies to another when incentives motivate combination.
A known automotive airbag sensor technique applied to consumer electronics shock protection — market pressures and design goals motivate the combination.
Test
Design problem was recognized; combination was known to be desirable; result is predictable
Rebutting Obviousness
Secondary Considerations (Objective Indicia of Non-Obviousness)
Even where motivation to combine exists, objective secondary considerations can rebut the prima facie case of obviousness. The patent owner must demonstrate a nexus between the secondary consideration and the specifically claimed features.
Commercial Success
Marketplace success attributable to the claimed invention's merits — not marketing alone. Requires proof that success is due to the patented features.
Long-Felt Need
The problem was recognized and unsolved for a substantial time despite others' awareness of it. Suggests non-obviousness of the solution.
Failure of Others
Skilled researchers tried to solve the same problem and failed before the inventor succeeded.
Industry Skepticism
Experts in the field said the approach wouldn't work or wasn't worth pursuing — yet the inventor proved them wrong.
Unexpected Results
The invention achieves dramatically better results than the prior art would predict. Often the most persuasive secondary consideration before the PTAB.
Copying by Competitors
After the invention was disclosed, competitors copied it rather than design around it — suggesting they found it difficult to independently arrive at.
FAQ
What is the motivation to combine in patent law?
In an obviousness analysis under 35 U.S.C. § 103, motivation to combine is the reason why a person of ordinary skill in the art (POSITA) would have combined two or more prior art references to arrive at the claimed invention. It is one of the Graham v. John Deere (S.Ct. 1966) factors that must be addressed in every obviousness inquiry: scope and content of prior art, differences between prior art and the claimed invention, level of ordinary skill, and any objective secondary considerations. Without a reason to combine the references, their mere existence in the prior art is insufficient to establish obviousness.
How did KSR change the motivation-to-combine standard?
KSR International Co. v. Teleflex Inc. (S.Ct. 2007) rejected the Federal Circuit's rigid 'teaching, suggestion, motivation' (TSM) test, which required finding an explicit suggestion in the references themselves or in the knowledge of a POSITA to combine them. KSR held that the obviousness analysis must be made in a 'flexible,' 'expansive' manner: a court may look to any reason that would have prompted a skilled artisan to combine the references — not just explicit teachings. KSR introduced five recognized rationale categories for combination and confirmed the 'obvious to try' concept when there are a finite number of identified, predictable solutions. KSR also emphasized that combining known elements using known methods to yield predictable results is likely obvious.
What are the five KSR rationales for combining prior art?
The five rationales recognized by KSR and codified by the USPTO in the 2007 KSR Guidelines: (1) COMBINING PRIOR ART ELEMENTS — combining known elements using known methods to yield predictable results; the combination is obvious when each element performs the same function it has in the prior art; (2) SIMPLE SUBSTITUTION — substituting one known element for another to obtain predictable results (e.g., replacing one type of fastener with another known fastener); (3) USE OF KNOWN TECHNIQUES — applying a known technique to a known device/method ready for improvement; (4) OBVIOUS TO TRY — choosing from a finite number of identified, predictable solutions with a reasonable expectation of success; applicable when the number of options is small and choosing among them yields no unexpected result; (5) KNOWN WORK IN ONE FIELD / DESIGN INCENTIVES — when prior art from one field can be applied to another, and the combination would be recognized by a POSITA as desirable to achieve a predictable result, and market/design incentives motivate combination.
What is 'obvious to try' after KSR?
'Obvious to try' is a legitimate rationale for obviousness under KSR when: (1) there are a FINITE NUMBER of identified, predictable solutions; (2) a person of ordinary skill has GOOD REASON to pursue the known options; and (3) the combination yields no more than predictable results. KSR example: if there are only three known seat-position adjustment mechanisms and only one had been combined with a particular pedal system, it would be obvious to try the others. However, obvious to try does NOT apply when the number of possible solutions is large or unpredictable, when the solutions are not all identified and recognized in the art, or when the result is unexpected or unpredictable. The Federal Circuit limits obvious-to-try to cases where discovery requires pursuing only a finite and predictable course.
How can secondary considerations rebut a finding of motivation to combine?
Graham v. John Deere requires consideration of objective secondary considerations (sometimes called objective indicia of non-obviousness): (1) COMMERCIAL SUCCESS — the invention's commercial success due to its merits (not just marketing); must show nexus between success and the claimed invention; (2) LONG-FELT BUT UNSOLVED NEED — the problem was recognized for years but not solved despite others' attempts; (3) FAILURE OF OTHERS — others tried and failed to achieve what the inventor accomplished; (4) INDUSTRY SKEPTICISM — experts in the field said it wouldn't work; (5) UNEXPECTED RESULTS — the invention achieves results not expected from the prior art (a particularly strong secondary consideration); (6) PRAISE — contemporaneous praise by experts or competitors at the time of the invention. To be persuasive, the patent owner must show a NEXUS between the secondary consideration and the specific claimed features of the invention.
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