Sufficiency of Invalidity Evidence in IPRs Can Differ for Method and Apparatus Claims

October 5, 2018

Using the same invalidity evidence to address apparatus and corresponding method claims in inter partes review (“IPR”) petitions can present difficulties depending on the claim language used in the apparatus claims.  In ParkerVision Inc. v. Qualcomm Inc., the Federal Circuit addressed these difficulties in affirming the U.S. Patent & Trademark Office’s Patent Trial and Appeal Board’s (“PTAB’s”) finding that ParkerVision’s apparatus claims were unpatentable but not the corresponding method claims despite the use of the same prior art evidence. (

      The Federal Circuit’s decision turned on whether the apparatus claims challenged in Qualcomm’s IPR petitions had elements reciting “capability” language or reciting “configuration” language.  Recognizing that “apparatus claims cover what a device is, not what a device does,” the corollary holds that “an apparatus that is ‘capable of’ performing certain functions may be anticipated by or obvious in view of a prior art apparatus that can likewise perform these functions.”  As a result, “a prior art reference may anticipate or render obvious an apparatus claim—depending on the claim language—if the reference discloses an apparatus that is reasonably capable of operating so as to meet the claim limitations, even if it does not meet the claim limitations in all modes of operation.”

      The claims at issue in ParkerVision’s patent recited an apparatus and method for frequency up-conversion in which the apparatus claims recited “a switch module to … generate a periodic signal having a plurality of harmonics,” and the method claims recited “gating a reference signal … to create a periodic signal having a plurality of harmonics.”  Addressing the apparatus claims, the Federal Circuit first determined whether the language recited “capability” or “configuration.”  Comparing the recited language to prior determinations on this issue, the Federal Circuit held that the apparatus claims “fall squarely on the ‘capable of’ side of the line.”  Since it was undisputed that the prior art device would necessarily produce a periodic signal containing integer multiples of the fundamental frequency under some but not all conditions, the prior art met all of the limitations of the apparatus claims including the “plurality of harmonics” limitation.  According to the Federal Circuit, “Qualcomm was neither required to identify the conditions under which [the prior art] device will output a plurality of integer-multiple harmonics nor obligated to explain why a person of skill in the art would have selected such operating conditions.”

      Although not required for the challenged apparatus claims, that was not the case for the method claims.  To render the method claims invalid, the Federal Circuit held that Qualcomm needed to present evidence and argument that a person of ordinary skill would have been motivated to operate the prior art device in a manner that satisfied the “plurality of harmonics” limitation.  Qualcomm’s petitions failed to do so.  Specifically, the petitions provided no evidence as to whether a person of ordinary skill in the art would have any reason to operate the prior art device with inputs that would produce the required “plurality of harmonics” nor provided any explanation or evidence as to why a person of ordinary skill in the art would have been motivated to select inputs for the prior art device circuit that would yield a periodic signal with a plurality of integer-multiple harmonics.  The Federal Circuit accordingly held that the method claims were not unpatentable.

      The Federal Circuit’s decision in ParkerVision affects the strategies that both petitioners and patent owners need to consider in post-grant proceedings.  For petitioners, all challenged apparatus claims need to be evaluated to determine whether they recite “capability” or “configuration.”  If determined to be “capability,” the petitioner can take advantage of the lower evidentiary threshold by showing through evidence and argument that the prior art is capable of performing the functions recited in the claims.  But if determined to be “configuration,” the petitioner needs to provide evidence and argument in the same manner as the method claims by showing that the prior art device is not only capable of performing the function (assuming it is not explicitly disclosed), but also why a person of ordinary skill in the art would have been motivated to configure the device to perform the function.

      For patent owners, the same analysis in reverse applies.  Specifically, if the challenged apparatus claims recite “configuration,” patent owners may be able to target the evidence and argument of the petitioner if the petition fails to demonstrate sufficiently that the prior art device is capable of performing the recited function or why a person of ordinary skill in the art would have been motivated to configure the device to perform the function. 

      Finally, for prosecution purposes, practitioners should understand the practical effects of using “capability” versus “configuration” language in apparatus claims.  “Capability” language has the advantage of broader coverage for infringement as an accused device can infringe as long as it has the capability to perform the recited functions.  At the same time, the “capability” language also subjects the claims to easier prior art invalidity attacks.  Conversely, “configuration” language requires the accused device to actually perform the recited function but also increases the difficulty of invalidity challenges.  Given those effects, practitioners need to determine which type of language is preferred or include independent claims that cover both types.