An inter partes review (“IPR”) proceeding allows a party to challenge the validity of a patent before the Patent Trial and Appeals Board (“PTAB”) of the U.S. Patent and Trademark Office (“USPTO”).1 In an IPR proceeding, invalidity challenges must be based on patents and printed publications. Printed publications must be admissible under the Federal Rules of Evidence and must qualify as prior art. This article reviews the process used by patent owners to challenge whether a reference qualifies as a prior art printed publication and how a petitioner can establish that a reference is a prior art printed publication and concludes with practical advice for both petitioners and patent owners in dealing with challenges to a reference’s status as a prior art printed publication.

Challenging Printed Publication Status at the Institution Stage

An IPR proceeding begins with the filing of a petition.2 The patent owner then has three months to file a preliminary response to the petition.3 Although the preliminary response is optional, it provides the patent owner an opportunity to argue that a reference cited in the petition does not qualify as a prior art printed publication.4

The PTAB decides whether to institute a trial within three months of the date that the patent owner’s preliminary response was due or was filed, whichever is first.5 The PTAB makes the determination based on the petition and the preliminary response, if filed. The petitioner does not have the opportunity to reply to the preliminary response at the institution stage, however, the petitioner may seek a rehearing if the PTAB does not institute a trial.

In deciding whether to institute a trial, the PTAB assesses whether there is a “reasonable likelihood” that the references relied upon in the petition qualify as prior art printed publications.6 This assessment involves a case-by-case inquiry into the facts of publication.7 Depending on the facts, a declaration from the author or other evidence may be needed to establish a reasonable likelihood of prior publication even at this early stage of the process.8

The PTAB’s review of a reference at the institution stage can be rigorous and typically involves more than a cursory review to see if the petitioner provided at least some evidence of prior publication. In one institution decision, the PTAB determined that the petitioner had not established a reasonable likelihood that an Internet reference qualified as prior art (despite the petitioner having submitted Internet archive data) due to insufficient evidence that a person of ordinary skill in the art could reasonably have found the reference.9 The PTAB noted that the petitioner failed to provide evidence about the group to which the Internet reference was posted, the members of the group, or the size of the group.10

In response, the petitioner sought a rehearing and submitted a declaration to supplement the evidence. The PTAB maintained its position, finding that the declaration was both insufficient and untimely, because it was not filed with the petition.11

Challenging Printed Publication Status Post-Institution

Even if the PTAB determines that there is a reasonable likelihood that the reference qualifies as prior art and therefore institutes the trial, the patent owner can still challenge the admissibility of the reference. The PTAB trial rules provide specific guidance with respect to the admissibility of USPTO documents and foreign language documents.12

In addition, the Federal Rules of Evidence apply to IPR proceedings and can be used to challenge the admissibility of evidence.13 For example, Federal Rule of Evidence 901(a) requires evidence to be authenticated as a pre-condition to admissibility. Certain self-authenticating documents require no extrinsic evidence of authenticity in order to be admitted.14 These types of documents include newspapers, periodicals, and trade inscriptions, such as articles inscribed with LexisNexis or USENET.15

Documents that are not self-authenticating, however, require sufficient evidence to support a finding that the item is what the proponent claims it is. As an example, printouts from a website are generally not self-authenticating, but they can be authenticated by an affidavit from a web master or other witness with personal knowledge of the website.16

With respect to challenges based on hearsay, it is important for a patent owner to specifically identify the portions of the evidence that constitute hearsay and sufficiently explain why.17 Hearsay challenges have limited applicability in IPRs to the extent the petitioner offers a reference as evidence of what the reference describes and not for proving the truth of the matters therein.18

Procedure for Objecting to Evidence as Inadmissible

To challenge the admissibility of evidence of prior publication, the patent owner first serves an objection on the petitioner.19 To object to evidence submitted during the preliminary proceedings, such as evidence of prior publication relied upon in the petition, the objection must be served within ten business days of the trial being instituted.20 The objection must identify the grounds for the objection with sufficient particularity to allow correction in the form of supplemental evidence.21

The petitioner responds to the objection by serving supplemental evidence within ten business days of the service of the objection.22 The PTAB encourages parties to resolve evidentiary issues between themselves.23 If upon receiving the supplemental evidence, the patent owner believes the issue has been resolved, the patent owner need not make the PTAB aware of the objection or the supplemental evidence.24 However, if the patent owner still believes that the evidence is inadmissible, the patent owner must file a motion to exclude the evidence in order to preserve the objection.25

Moving to Exclude Inadmissible Evidence

Authorization to file a motion to exclude is automatically granted and does not require a conference with the PTAB.26 A motion to exclude must (a) identify where in the record the objection was originally made; (b) identify where in the record the evidence sought to be exclude was relied upon by an opponent; (c) address objections to exhibits in numerical order; and (d) explain each objection.27 The supplemental evidence that was served during the objection process can be submitted to the PTAB as an exhibit to the motion to exclude or the opposition thereto.28

The time for filing the motion to exclude is set in the Scheduling Order.29Typically the time for filing the motion to exclude is several months into a trial.30If the patent owner fails to move to exclude a prior art reference as provided in the Scheduling Order, the PTAB will not exclude the reference.31 The Scheduling Order also provides dates for the petitioner to file an opposition to the motion to exclude and for the patent owner to file a reply to the opposition.32 The PTAB then decides the motion using a preponderance of the evidence standard.33 The burden of proof is on the patent owner as the party seeking to exclude the prior art reference on the grounds of inadmissibility.34

Challenging the Sufficiency of Prior Publication Evidence

According to the rules, a motion to exclude only addresses admissibility.35Thus, a patent owner seeking to challenge the sufficiency of the evidence to prove the publication date of the reference should do so in the Patent Owner Response.36 In practice, the issues of admissibility and sufficiency of the evidence can be interrelated, and the PTAB has considered sufficiency issues, such as the accessibility of a reference to a skilled artisan, in the context of a motion to exclude.37 Thus, a patent owner should carefully consider the reasons for excluding a reference to determine whether to challenge the reference in a motion to exclude, the Patent Owner Response, or both.

The petitioner has the burden to prove that a reference qualifies as a prior art printed publication. For support, the petitioner is generally limited to evidence included in the petition. However, the petitioner may request authorization to file a motion to submit supplemental information.38 If more than one month has elapsed from the date that the trial was instituted, the motion must show why the supplemental information reasonably could not have been obtained earlier and that consideration of the supplemental information would be in the interest of justice.39

Practical Considerations

Though the jurisprudence at the PTAB is continuing to evolve, the preceding review of rules and cases raises a few considerations for both petitioners and patent owners. First, while the “reasonable likelihood” standard that the PTAB applies during the preliminary stage may require a lesser showing with respect to prior publication than the “preponderance of the evidence” standard applied during the trial stage, both petitioners and patent owners should be aware that prior publication issues raised by the patent owner in the preliminary response will be reviewed by the PTAB during the preliminary stage. Thus, it may be beneficial for a patent owner to raise such issues (e.g., whether a reference was reasonably accessible) with some particularity in its preliminary response even if the patent owner plans on raising the issues post-institution; it can lead to a reference being excluded from the trial even if the petition is instituted. By the same token, when preparing a petition, the petitioner should critically examine references that are not automatically admissible under the Federal Rules of Evidence (e.g., printed publications that are not taken from periodicals, such as Internet websites or product manuals) or that may require extrinsic evidence to establish that they qualify as a prior art printed publication. Petitioners should also consider performing a supplemental search to identify a reference disclosing similar subject matter that does not have authentication issues, such as a patent reference. This may reduce the effort required in the IPR proceeding to demonstrate that the reference is admissible and qualifies as a prior printed publication.

In the petition and accompanying exhibits, petitioners should strongly consider including evidence, testimony, and/or arguments that clearly demonstrate that a reference was published prior to the critical date and that it was reasonably accessible to one of ordinary skill in the art. If this is not done, petitioners risk the PTAB denying institution of the trial on grounds that rely on such references and may forego their ability to present evidence or arguments in a rehearing if it was reasonably possible for petitioners to have included such material in the petition.

Post-institution, both petitioners and patent owners have an opportunity to use discovery afforded in the proceedings to further vet whether a reference is a prior art publication. However, patent owners and petitioners need to carefully review the timeline of the proceeding to ensure they have enough time to obtain evidence or testimony needed to address these issues. Declarations and depositions of third parties (such as those that are not retained as experts) can be time consuming to obtain. To the extent possible, it is recommended that petitioners obtain evidence of prior publication before filing the petition and include the evidence in the petition. When that is not possible, petitioners should work on supplementing the evidence shortly thereafter so that evidence needed to clearly demonstrate that the reference as a prior art printed publication is available if and when the issue is raised.

While IPR proceedings may not include many of the evidentiary issues that can arise in district court litigation due to the limited nature of prior art available in the proceedings, petitioners and patent owners should be aware that the Federal Rules of Evidence still apply. Indeed, admissibility issues may become more frequent in IPR proceedings as petitioners increasingly use prior art from the Internet. Petitioners and patent owners should pay careful attention to whether a reference qualifies as a prior art printed publication.