PTAB: Expert’s Factual Bases Fair Game for Additional Discovery, but Communications with Counsel Are Off Limits

Oct 25, 2021

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Pursuant to the PTAB’s authorization and 37 C.F.R. § 42.51(b)(2), the patent owner requested four categories of additional discovery. Requests 1 and 4 sought the protocols and results of experiments conducted by the petitioner’s expert. Requests 2 and 3 sought “documents identifying, including, or referring to” instructions provided to the petitioner’s expert concerning the design and parameters of the experiments.

The patent owner argued that additional discovery into the experimental parameters, and possible instructions from counsel for selecting those parameters, would be useful for assessing the petitioner’s inherent anticipation argument. In its opposition, the petitioner indicated it would produce documents about the experimental parameters for characterizing the two prior art references at issue in the IPR, but argued that correspondence between the petitioner’s counsel and expert related to the design of the experiment were protected work product.

To assess whether granting additional discovery would serve the interests of justice, the PTAB applied the Garmin factors. Garmin Int’l, Inc. v. Cuozzo Speed Techs. LLC, IPR2012-00001, Paper 26 at 6–7 (PTAB Mar. 5, 2013) (precedential).

Under the first Garmin factor, the PTAB considered whether there was more than a mere possibility that additional discovery would yield useful information—namely, information “favorable in substantive value to a contention of the party moving for discovery,” and not merely relevant or admissible. The PTAB concluded that Requests 1 and 4 fell squarely within routine permissible discovery, as the requests inquired about the facts and prior art references that the petitioner’s expert considered in preparing his testimony. The PTAB observed, “it makes no sense to us to deny the document discovery requested here and then permit it in [the petitioner’s expert’s] deposition.”

In contrast, the PTAB found that the first Garmin factor did not support granting additional discovery as to Requests 2 and 3. The PTAB noted that the patent owner had provided no basis for its belief that opposing counsel had instructed petitioner’s expert to use particular parameters in his experiments. Furthermore, although the Federal Rules of Civil Procedure do not apply to IPR proceedings, the PTAB found that granting Requests 2 and 3 would be both impermissible under PTAB rules and inconsistent with Rule 26(b)(4)(C). Requests 2 and 3 sought not only documents that identify material discoverable under Rule 26(b)(4)(C)—namely, communications between a party’s attorney and expert related to the expert’s compensation or facts, data and assumptions considered by the expert—but also documents that merely include or refer to that discoverable material.

As to the second Garmin factor, the PTAB concluded that Requests 1 and 4 did not impermissibly seek petitioner’s litigation positions or the underlying bases for those positions. The PTAB found that Requests 1 and 4 were fair in that they sought information that the petitioner’s expert considered in testing reconstructions that formed part of petitioner’s case-in-chief. On the other hand, the PTAB found that the second factor weighed against granting Requests 2 and 3, and reiterated that these requests sought information outside the scope of the PTAB’s rules.

The PTAB found that the third and fourth Garmin factors weighed in favor of granting the motion for additional discovery, as none of the requested information could be generated by other means, and the additional discovery requests were easily understandable.

Finally, under the fifth Garmin factor, the PTAB considered whether the requests were overly burdensome, “given the expedited nature of inter partes review, including financial burden, burden on human resources, and burden on meeting the time schedule.” The PTAB concluded that Requests 1 and 4 were limited in scope and therefore not overly burdensome for the petitioner to answer. However, the PTAB found that attempting to answer Requests 2 and 3 without revealing protected attorney work product would be overly burdensome to the petitioner.

The PTAB noted that the petitioner did not specifically address factors 3, 4 and 5 in its opposition briefing.

In light of its analysis of the Garmin factors, the PTAB granted the patent owner’s motion for additional discovery as to Requests 1 and 4, but denied the motion as to Requests 2 and 3.

Practice Tip:

A party seeking additional discovery in an IPR proceeding must show that granting the request is in the interests of justice under the Garmin framework. Requests for documents showing the factual bases of an expert’s testimony are typically permissible as providing useful information (factor 1) that is not merely the opposing party’s litigation positions (factor 2) and that cannot be generated by other means (factor 3). However, the party seeking discovery should carefully draft such requests to not run afoul of protections afforded to attorney work product. In addition, the party opposing discovery should expressly argue why each Garmin factor disfavors the requested discovery.

Tennant Co. v. Oxygenator Water Techs., Inc., IPR2021-00625, Paper 30 (PTAB Oct. 18, 2021)

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