Close, But Not Close Enough: Analysis of “Near Fit” Prior Art

By: A. Rusty Rogers


In a recent decision, the U.S. Federal Circuit unearths a 19th century opinion to highlight the bedrock principle that anticipation requires showing that all elements of a claimed invention existed in the prior art, without the need for distortion or selective modification of a prior art reference.

Anticipation under 35 U.S.C. § 102 is established when a prior art reference describes every claim limitation and enables one of skill in the art to practice an embodiment of the claimed invention without undue experimentation.  While some modification may be appropriate in the context of obviousness under 35 U.S.C. § 103, this section has its own distinct requirements and body of associated case law.  Nevertheless, examiners in some instances interpret the content of the prior art in their favor to cover over gaps in their analysis.  For example, an examiner may take an image out of context or omit qualifying language to expand a fact-specific statement in a general way that encompasses unrelated concepts and technologies.  In other cases, claim language may be construed more broadly than presented by an applicant to force a rejection using prior art that is a “near fit” to the claimed invention, usually under the guise that the claims are to be constructed by the PTO or PTAB according to their “broadest reasonable interpretation” (BRI).

In a recent decision, In re Chudik, 2016-1817 (Fed. Cir. 2017) before Dyk, Reyna, and Stoll, Inventor Chudik appealed from a final rejection at the Patent Trial and Appeal Board (PTAB).   The issue surrounds a number of apparatus claims directed to an implant for shoulder replacement surgery that requires “a protruding surface . . . arranged to engage the surface” of a cavity within the shoulder joint.  The Patent and Trademark Office (PTO) rejected all claims as anticipated by prior art references.  On appeal, the rejection was affirmed at the PTAB, which agreed with the Examiner’s finding that, while “arranged to engage” was broadly interpreted by the examiner to read on structures that do not engage the recited surfaces, the interpretation was permissible because the claims did not require actual engagement with surfaces within a shoulder.   The PTAB noted that, while protruding and flat surfaces of the prior art were not described or depicted as actually engaging the specified glenoid regions, lack of actual engagement was not dispositive, as elements could still be arranged to do so.

Chudik appealed to the Federal Circuit, arguing that the prior art does not anticipate the claims at issue without improper modification thereof.  Specifically, noting that the prior art had to be distorted from its original design to conceivably anticipate the new invention. The Federal Circuit agreed with Chudik’s arguments and reversed the PTAB’s decision, noting that the Board failed to describe how a user could perform the asserted modification of the prior art while continuing to accomplish the function performed by the original application.  Modifications required to find anticipation were remarkably extensive; a prominent example being a rejection premised on anticipation that required a user to rotate the prior art device 180 degrees and relocate screws used to attach the prosthetic to the shoulder to remain operable.

Highlights from the decision include a discussion of the importance that anticipation be based on the actual content of the prior art. “Simply put, an anticipated invention ‘is not new’” (citing In re Skvorecz, 580 F.3d 1262, 1267-68 (Fed. Cir. 2009).  The Federal Circuit also pointed out that modification of the reference to find anticipation is impermissible, a concept rooted in antiquity – “It is not sufficient to constitute an anticipation that the device relied upon might, by modification, be made to accomplish the function performed by the patent in question, if it were not designed by its maker, nor adapted, nor actually used, for the performance of such functions.” Topliff v. Topliff, 145 U.S. 156, 161 (Commr. Pat. 1892)(emphasis added).  Tying this principle to the facts, the Federal Circuit noted that a prior art device must be at least capable of engaging with the shoulder cavity to meet the claim limitation of “arranged to engage,” and that the cited references only anticipate by modification to omit or rearrange parts in such a way that portions of the respective devices became unusable or substantially misaligned.  The decision concluded by finding that the PTAB lacked substantial evidence for its findings and reversed in favor of Chudik.

From a practitioner’s perspective, it is important to carefully review all references cited by an examiner when an office action is received.  Given the almost adversarial relationship between the client and examiner during the patent application process, it is often beneficial to ignore conclusory language used to construct claim rejections and verify any sections in the prior art cited by the examiner in formulating the rejection.  When responding to a claim rejection, it is important to consider what assumptions are being made by the PTO, particularly the (1) characterization of the content of the prior art, and (2) the interpretation of the language of the claims at issue.  Because the PTO holds the burden of establishing that claims are not patentable, a properly formulated rebuttal to a poorly constructed rejection under § 102 can lead to allowance in some cases, or at least force the examiner to find new prior art or reformulate the rejection under § 103.

In re Chudik illustrates point (1) perfectly in the context of anticipation: the reference must disclose the exact invention, not merely be close with slight modifications, regardless of how minor or trivial.  To this end, each limitation of a claimed invention must be present in the prior art, and it is not sufficient that one skilled in the art could modify a reference with the benefit of hindsight using Applicant’s specification as a blueprint.  In addition to pointing out any impermissible modifications to the prior art, a complementary technique noted in point (2) is identifying when the PTO is abusing BRI to read meaningful limitations out of a claim in order to bolster a rejection in view of an imperfect reference.  In Chudik, for example, the examiner improperly interpreted “arranged to engage” as broadly including not only structures that could engage the shoulder surface, but also any structure that could conceivably be rearranged or modified into some form of engagement.

Effective responses in these scenarios include spotting weak links in the rejection, usually identified as conclusions with little or no analysis, or express statements that claim elements are being interpreted broadly (often couple with assertions that limitations will not be read into the claims).  When these patterns are recognized, it is important to point out how the reference and/or claim elements are being mischaracterized, and re-framing the argument in a way that is both supported by evidence and in the best light for the client.