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PTAB Reinforces Uneven Evidentiary Playing Field in IPRs

The U.S. Patent and Trademark Office’s Patent Trial and Appeal Board (PTAB) recently grappled with the admission into evidence of expert deposition testimony that was presumably harmful to the petitioner in an inter partes review (IPR), and barred the testimony from coming into evidence.  In Axonics Modulation Technologies, Inc. v. Medtronic, Inc., Cases IPR2020-00678, IPR2020-00680, IPR2020-00712, Paper 22 (April 9, 2021), the petitioner elected to depose patent owner’s expert, but then declined to submit the transcript as an exhibit to the petitioner reply.  The patent owner then attempted to submit the transcript as an exhibit to the sur-reply, but the PTAB refused to receive deposition testimony.  This case demonstrates the uneven evidentiary playing field for patent owners and petitioners, as the rules would apparently allow the reversed situation to occur.  Specifically, while patent owners are barred from submitting new evidence in a sur-reply, petitioners are expressly allowed to do so, thus if a patent owner declines to submit deposition testimony of a petitioner’s expert with the patent owner response, the petitioner may submit that transcript anyways as part of the petitioner’s reply.   

The PTAB’s analysis is instructive of the evidentiary disparity, as it appears to have followed the rules to the letter.  The patent owner argued that the petitioner should be required to file the transcript as an exhibit to its reply pursuant to 37 C.F.R. § 42.53(f)(7).  Section 42.53(f)(7) requires only the proponent of the testimony to file the transcript as an exhibit; it does not require the party to use any exhibits at all.  Although petitioner deposed patent owner’s expert, petitioner chose not to rely on that testimony, and did not enter the transcript as an exhibit.  The PTAB held that because the petitioner was not the proponent of the transcript, petitioner was not required to file the transcript.

The PTAB also denied patent owner’s request to file the transcript as an exhibit with its sur-reply.  As the Patent Trial and Appeal Board Consolidated Trial Practice Guide (“CTPG”) explains, a sur-reply “may not be accompanied by new evidence other than deposition transcripts of the cross-examination of any reply witness.”  CTPG, 73.  Because petitioner did not rely on or cite to the testimony in question, the PTAB determined that the testimony did not constitute a cross-examination of a reply witness.  Further, 37 C.F.R. § 42.23(b) provides that “[a] reply may only respond to arguments raised in the corresponding opposition or patent owner response.”  The PTAB reasoned that the inclusion of the transcript in patent owner’s sur-reply would not have been in response to any such argument raised by petitioner because the petitioner did not address the testimony of the expert.  The PTAB found that allowing the testimony to be introduced as evidence as part of patent owner’s sur-reply would be akin to introducing an untimely supplemental declaration to support its sur-reply.

This case further demonstrates that patent owners should not rely on deposition testimony of their expert to fill holes that may otherwise exist in their case.  If the patent owner’s expert needs to say something or disclose a specific opinion, the best practice is to make sure that the statements and opinions are clearly contained within the four corners of the expert declaration submitted with the patent owner’s response. 

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Daniel Weinger

Nana Liu


Nana Liu is a Mintz attorney who focuses on intellectual property litigation for life sciences companies. She handles cases in federal courts, the US Court of Appeals for the Federal Circuit, and the International Trade Commission (ITC), as well as Hatch-Waxman pharmaceutical cases.