United States: Challenging "Obvious To Try" During Patent Prosecution

Suppose your client's patent application is rejected as allegedly obvious under 35 USC §103, and the Examiner cites one or more references and sets forth an "obvious to try" rationale in an Office action.  Here are some tools you can add to your toolkit, and possibly apply to challenging the Office assertion that the claimed invention is "obvious to try" in light of the cited reference(s).  Of course, arguments should be tailored to the circumstances at hand, an amendment might help, and it is not necessarily the case that all (or even any) of the following arguments will apply in all scenarios.

We may rely on advice the Manual of Patent Examining Procedure (MPEP) dispenses in 2143 "Examples of Basic Requirements of a Prima Facie Case of Obviousness":
E. "Obvious To Try" – Choosing From a Finite Number of Identified, Predictable Solutions, With a Reasonable Expectation of Success
To reject a claim based on this rationale, Office personnel must resolve the Graham factual inquiries. Then, Office personnel must articulate the following:

(1) a finding that at the time of the invention, there had been a recognized problem or need in the art, which may include a design need or market pressure to solve a problem;
(2) a finding that there had been a finite number of identified, predictable potential solutions to the recognized need or problem;
(3) a finding that one of ordinary skill in the art could have pursued the known potential solutions with a reasonable expectation of success; and
(4) whatever additional findings based on the Graham factual inquiries may be necessary, in view of the facts of the case under consideration, to explain a conclusion of obviousness.

Relating to (1) above, has the Office action produced a factual showing in the cited reference(s) of the "recognized problem or need in the art"?  If not, this can be challenged.  For example, there is a silence in the reference as to the alleged recognized problem or need in the art, and the Office has not produced such a factual showing.

Relating to (2) above, has the Office action produced a factual showing in the cited reference(s) of "a finite number of identified, predictable potential solutions"?  If the reference does not show the specific combination of elements or interrelationships among the elements recited in the claims of the Applicant (e.g., there would've been a 35 USC §102 rejection as anticipation), the reference likely shows a finite number of other arrangements or interrelationships among some of the elements recited in the claims of the Applicant.  But, how many ways can these elements be rearranged or interrelated?  Is this finite, or infinite or semi-infinite?  Does the reference teach or suggest any guidance as to other arrangements or combinations of these elements?  You may be able to argue that the reference shows certain elements, which could be rearranged in an infinite or semi-infinite number of ways.  If the reference shows only a few specific arrangements or combinations, and doesn't provide guidance as to the rest of the possibilities, you may be able to argue as follows.  The claimed arrangement or combination is not specifically shown among the finite number of identified potential solutions in the cited reference.  What remains as to other possible arrangements or combinations of these elements is semi-infinite or infinite, and is therefore not shown in the reference as a finite number of identified potential solutions.

Relating to (3) above, has the Office articulated a motivation that directs the person of ordinary skill in the art in an appropriate direction to pursue the known potential solutions?  If the motivation cited in the Office action is general in nature, this can be challenged as not distinguishing among a very large number of possible combinations of the elements and therefore not directing towards a reasonable expectation of success to the particular problem which Applicant addresses.  For example, a motivation to improve could be pursued in any of a very large number of directions with not only the elements cited in the Office action but many further elements besides, and might not constitute a factual showing of how the person of ordinary skill in the art could have pursued the known potential solutions with a reasonable expectation of success that leads to the claimed limitations.

Relating to (4) above, what does the Office action say about the gaps between what is shown in the cited references and the claimed device, system or method, etc.?  This is often where the opportunity for an amendment arises.  Sometimes, a clarifying amendment, which highlights such a gap but does not unduly narrow a claim, is a good approach to pursue.  This can strengthen arguments.

Let's work through an hypothetical example that may provide insights as to the above processes.  Applicant has discovered that arranging elements A and B at a particular angle and applying C in a range of positions relative to A and B solves a specific problem.  The references cited in the Office action show elements A, B and C, but A and B are always parallel (i.e., not at the particular angle) and C is shown performing some function unrelated to what A and B are doing.  The Office action rejects the claim as "obvious to try" in light of the showing of A, B and C in the cited references.

This can be challenged as follows.  The cited references do not identify the specific problem solved by Applicant, nor do the cited references show the specific solution arrived at by Applicant.  Although the cited references show A and B, these are always in parallel arrangement which teaches away from the angular arrangement applied and claimed by Applicant.  Moreover, A and B could be arranged at an infinite number of possible angles and relative positions, so the cited references do not show a finite number of possible solutions.  The cited references are silent as to the advantages of arranging A and B at angles other than in parallel and so do not teach a range of predictable potential solutions to various problems.  The cited references do not show the relationship of C to A and B, so the aspects of the claimed relationship of C to A and B are not shown in the possible solutions identified in the cited references.  Any or all of the above can be argued as challenges to the "obvious to try" rationale.

Similar examples can be set up for electronics circuits, mechanical devices, electromechanical devices, software and hardware systems, methods (this may be useful for software-based patenting), material layers, biochemistry and numerous other types of subject matter.  Moreover, the above analysis and toolkit building for patent prosecution can be applied to other rejection rationales.  Just look up in the MPEP and see what the Examiner is supposed to do to make a proper rejection.  Pay attention to the details.  Then, see if there are opportunities for challenging or amendment during patent prosecution.  This is all part of the art of patenting.

The content of this article is intended to provide a general guide to the subject matter. Specialist advice should be sought about your specific circumstances.

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