Non-Analogous Art Can’t be Obvious


Many of my recent posts have been concerned with whether a development is eligible for patent protection.  This is a Section 101 question.  Recall that laws of nature, natural phenomena and abstract ideas without more are not eligible for patent protection.  Other hurdles of patenting are whether the development is novel (Section 102) or whether the development would be an obvious modification of existing art in the eyes of a person skilled in the relevant technology (Section 103). See articles Section 103 Obviousness Rejections and 103 Obviousness Rejections II.

What is obvious to a person skilled in the art is hard to determine from objective evidence.  With hindsight, everything looks like an obvious next step.  However, the examiner are told not to use hindsight analysis.  (Realistically, how can they not?)

Examiners are allowed to project “common sense” into the developmental process.  This is a nebulous exercise.  Obviousness rejections are very common and often revolve around subjective factors.

One standard is that the conclusion that the development is an obvious step CANNOT look to non-analogous art.  Merriam Webster defines analogous as “similar or comparable to something else either in general or in some specific detail” or “similar in a way that invites comparison : showing an analogy or a likeness that permits one to draw an analogy”. 


Patent law is clear that non-analogous art or technology cannot be asserted as a basis for rejecting the developmental as obvious to a person skilled in the relevant art or technology.  See for example Innovention Toys, LLC v. MGA Entertainment, Inc. decided in 2011.  

The patent law has developed a specific test for determining whether the art referenced by the examiner is analogous. First, the examiner’s referenced art must be in the same field of endeavor as the claimed invention.  The second alternative test is whether the examiner referenced art is reasonably pertinent to the particular problem faced by the inventor.  See the 1979 case entitled In re Bigio.

First Test

In regard to the first test, i.e., same field of endeavor, the description of the invention/development contained within the application specification may be key.  It is helpful if the application is drafted to solve a particular problem in a particular technology.  Unnecessarily broad or open language will be a hindrance to the applicant’s later argument against the examiner that the cited art is not in the same field of endeavor. However, the law is helpful in stating that the examiner must assemble substantial evidence of facts to support the assertion of a common field of endeavor.  In re Gartside decided in 2000 and In re Bigio decided in 2004.  For example, the examiner must show that the referenced art and the invention “have essentially the same function and structure”. 

Note, as suggested above, the determination of whether the examiner’s referenced art is analogous may involve scrutiny of the applicant’s specification (in contrast to only the text of the claims).  

Second Test

In regard to the second test, the standard is a bit more murky.  The examiner cited reference may be in a different field of endeavor but still analogous if it, by the nature of the problem faced by the applicant, would have commended itself to the inventor’s attention.  The 2011 decision of In re Klein states “if a reference disclosure has the same purpose as the claimed intention, the reference relates to the same problem, and that fact supports use of that reference in an obviousness rejection.”

Again, the text of the specification may be critical.  Hopefully it describes the purpose of the relevant limitations of the application (these limitations or elements being part of the claims). 

Note this topic is discussed in Section 2141.01(a) of the Manual of Patent Examination and Procedure (MPEP).  This section states:  “Any argument by the applicant that the examiner has misconstrued the problem to be solved, and as a result has improperly relied on non-analogous art, should be fully considered in light of the specification.  In evaluating the applicant’s argument, the examiner should look to the teachings of the specification and the inferences that would reasonably have been drawn from the specification by a person of ordinary skill in the art as a guide to understanding the problem to be solved.”

Recent Activity

Finally, in a case decided in early 2018, the Court of Appeals for the Federal Circuit (CAFA) determined that prior art pertaining to winding glass fiber would not be art considered by a person skilled in a technology pertaining to arthroscopic surgery generally and cutting semi-rigid tissue specifically.  See Smith & Nephew Inc. v. Hologic, Inc.  The Court acknowledged that both the examiner’s reference and the applicant’s invention used similar mechanical solutions but that the Court was not convinced that a person working to solve an arthroscopic surgical device problem would logically consider the prior art cited by the examiner directed to winding glass fiber strand to form packages.  The subject of the technologies were viewed as completely different.  The prior decision of the Patent Trial and Appeal Board (PTAB) was overturned.  

In contrast to the CAFC, the PTAB had stated that one examiner’s reference was “relevant to solving the technical problem of converting rotation motion into simultaneous rotational, translational, and reciprocal motions” and a second reference was relevant to adjusting the shape of a cam groove to vary the number or reciprocations per rotation.  

The claim describing the arthroscopic surgical device included “a drive coupled with a cutting member to simultaneously rotate, translate and reciprocate the cutting member  . . . . the drive member including a helical groove, and drive includes a translation piece disposed in the groove such that rotary driving of the drive member results in simultaneous reciprocation . . . “


The standards imposed upon an examiner’s rejection of obviousness have been considered to have been loosened in recent years.  However, the examiner’s reach into different technology can not extend beyond what the person reasonably skilled in the relevant art would have considered for finding a solution.  Stated differently, the examiner can not reach to technology that would be obscure to the practitioner.  

I suggest the burden remains upon the examiner to “connect the dots” to show why the person reasonably skilled in the relevant art would look to the distant and unrelated technology to find an obscure technique.  

Copyright David McEwing, 2019