PTAB Year in Review – Caveat Experimenter: Using Experimental Data in PTAB Proceedings Comes With Risks

Parties involved in Patent Trial and Appeal Board (PTAB) proceedings sometimes contemplate submitting experimental data to support their positions. Although such data can be useful, there also are risks. Several recent cases highlight the risks and benefits associated with submitting test data in PTAB proceedings.

Track the Art Closely

SNF S.A. v. Chevron USA, Inc., IPR2022-01534¹, highlights the strict standards the PTAB applies when assessing test results relied upon to show inherency. In SNF, the challenged claims recited a method for preparing an inverted polymer solution having a “filter ratio of 1.5 or less.” Id. at 7. Notably, the claims did not recite a “dewatering” step. Id. To support the petition, petitioner’s expert conducted experiments purporting to demonstrate that the prior art “Li” reference disclosed a method for preparing inverted polymer solutions inherently meeting the claimed filter ratio limitation. Petitioner’s expert provided experimental data for the filter ratio obtained both before and after a “dewatering” step optionally included in the method used in several examples in Li. Id. at 25. All of the exemplified “before dewatering” tests failed to meet the claimed filter ratio, which was met only after including a “dewatering” step. Id. at 27. In finding that the petitioner failed to prove inherent antici-pation,² the PTAB noted:

Neither Petitioner nor Dr. Barati provide any persuasive evidence supporting why Dr. Barati calculated filter ratios both “before dewatering” and “after dewatering,” but relied only on the “after dewatering” data to support its argument that the challenged claims are anticipated by Li. Li’s examples, however, provide no disclosure of a dewatering step. Moreover, we have not been directed to persuasive evidence that using a dewatering step in Li’s examples was inherent in Li’s disclosed procedures.

Id. at 26. Indeed, at his deposition, the petitioner’s expert testified that he did not rely solely on Li for the dewatering step, but relied on other references also. Id. Ultimately, the PTAB concluded that petitioner failed to meet its burden to show inherency because there were “too many unanswered questions” about the variables petitioner’s expert chose to test in attempting to show inherency using the Li reference. Id. at 27.

SNF serves as a reminder to practitioners that laboratory testing used to establish inherency should track the prior art disclosure with precision. Here, the petitioner relied upon the prior art’s disclosure of various examples, but failed to establish that those examples included the dewatering step that was necessary for satisfying the claim limitations.

Petitioner’s tests also faced additional avoidable criticisms from the patent owner, e.g., that petitioner’s expert failed to disclose the source or verify the contents for nearly all of the starting materials he used, and he purported to have taken almost no written recordings or observations for his experiments. To this end, parties should be mindful of the requirements under 37 C.F.R. §42.65 to provide a fulsome explanation of their tests and data.³

Do the Right Test

It should go without saying that it is important to do the right test to establish inherency. But this is precisely the error that befell the petitioner in Pioneer Pet Products, LLC v. Oil-Dri Corporation of America, IPR2022-01138.⁴ There, the patent claims were directed to:

A [cat] litter comprising: 45% to 80% by weight of sodium bentonite, wherein the sodium bentonite comprises at least 47% of an external surface area of the litter [the “47% surface area limitation”]….

Id. at 6. To establish that the “47% surface area limitation” was inherently disclosed in the prior art publication by House, petitioner argued that “[b]y virtue of House disclosing its litter contains a maximum of 80% by weight of sodium bentonite SCWEOS [“smectite clays which exhibit osmotic swelling”], a PHOSITA would have recognized that House at least inherently meets the claim limitation of ‘at least 47% of the total external surface of the litter.’” Id. at 46. The PTAB noted that petitioner relies on declarant testimony that essentially repeated the arguments from the petition. Id. at 45.

The PTAB found that petitioner failed to prove by a preponderance of the evidence that House expressly or inherently discloses the 47% surface area limitation. Id. at 46. Noting that the petition “provides a single sentence of analysis of the limitation that contains several flaws,” the PTAB found that “the argument improperly conflates weight percent and percent surface area by suggesting that a given weight percent alone will inherently disclose a certain percent surface area…. [T]he two measurements are not the same, and the Petition provides no argument or evidence linking the weight percent of sodium bentonite to any specific external surface area of that material.” Id. The PTAB went on to state, “To make matters more confusing, the body of the argument in the Petition suggests that the 80% by weight of sodium bentonite leads to the 47% surface area limitation, but the claim chart summarizing the challenge suggests that litters having either 50% or 65% by weight of sodium bentonite leads to the 47% surface area limitation.” Id. at 46–47. This case illustrates the PTAB’s close attention to technical details and the need for parties and their counsel to do the same. In view of this and other flaws, the PTAB found the petition failed to meet the 47% surface area limitation. Id. at 49.

The petitioner also attempted to “fill the holes in the Petition by relying on new calculations and test data in its reply,” but the PTAB did not view consideration of this new reply evidence as proper. Id. at 48. Rather, the PTAB found that the reply “introduces what amounts to new theories based on new portions of House never specifically identified in the Petition, as well as evidence that goes well beyond House’s disclosure” and the PTAB declined to consider them. Id. at 49. The PTAB concluded that petitioner failed to prove anticipation. Pioneer underscores the importance of doing the proper test and analysis the first time, as the PTAB may disregard belatedly presented evidence.

Be Ready for Discovery

A party relying on test data may find that it is on the receiving end of a motion for additional discovery as the opposing party might probe for weaknesses. In Syngenta v. UPL, PGR2023-00017,⁵ the petitioner conducted tests to support allegations regarding lack of synergy to refute non-obviousness and to show a lack of enablement. The petitioner originally produced data relating only to one of four assessed parameters. In response, the patent owner moved to compel disclosure of data relating to all parameters assessed in the same experiments, asserting that the information sought contradicts petitioner’s arguments.⁶ In ruling to compel such discovery, the PTAB stated:

While petitioner contends that only some of the data from these tests, i.e., the severity data, is relevant, we do not agree that petitioner can effectively prevent patent owner from testing that assertion by withholding production of the rest of the data, [relating to other parameters,] from the same experiments…. That additional data is directly relevant to the factual allegations in this proceeding whether it supports patent owner’s arguments regarding enablement and unexpected results or is simply consistent with the testimony . . . and petitioner’s other factual assertions.

Id. at 3. Thus, a party seeking to rely on test results should be prepared for the possibility that they will have to disclose other, related tests even if that party deems such tests irrelevant. After obtaining the requested discovery in Syngenta, the patent owner and its expert asserted that the underlying test data demonstrated synergy for the claimed subject matter. However, at oral argument, counsel for patent owner acknowledged that the data its expert analyzed in forming his opinions on synergy did not fall within the scope of the challenged claim. As such, the PTAB found that there was no nexus between the data and the challenged claims and it therefore did not consider the patent owner’s expert’s opinions on synergy in determining obviousness.

Don’t Try to Hide

Parties considering conducting testing should familiarize themselves with Spectrum Solutions v. Longhorn Vaccines and Diagnostics, IPR2021-00847, including Director Vidal’s sua sponte Director Review decision, lest they risk getting caught by the horns.⁷ Director Vidal elected to review the PTAB panel’s Final Written Decision so that she could address which regulations are implicated when a party withholds relevant factual evidence during an AIA proceeding. Director Review Decision, 3. In Longhorn, the patent owner submitted laboratory test data addressing whether the prior art taught certain claim limitations. Id. at 5. On cross-examination of the declarants, patent owner’s counsel instructed its witnesses not to answer certain questions, asserting work product immunity. Id. The petitioner promptly sought—and was granted—additional deposition time after the parties briefed the PTAB on the applicability of work-product immunity regarding the unanswered deposition questions. Id. Additionally, the PTAB ordered the patent owner to serve petitioner with any relevant inconsistent information. Id; See 37 C.F.R. §42.51(b)(1)(iii). Upon obtaining the additional documents, petitioner found that patent owner had submitted data only for certain tested pathogens and assays, while withholding other, conflicting data. Id. at 6. And to make matters worse, the patent owner also withheld the conflicting data from its own expert. Id. at 19.

In Longhorn, the patent owner’s efforts to hide behind the work-product doctrine were to no avail, because the PTAB held it “cannot be used to shield factual information from discovery that is inconsistent with positions taken by a party before the Board,” because doing so violates the party’s duty of candor and good faith to the Office. Id. at 23. Moreover, the PTAB found that the patent owner waived any immunity over the withheld data. Id. at 27. The PTAB noted that the patent owner could have filed the withheld test results under seal, requested in camera review, “provided a privilege log identifying the withheld [] Data,” or “produc[ed] a redacted copy” so the petitioner and PTAB would be on notice of the existence of other test results. Id. at 30. The patent owner’s strategic decisions and conduct in Longhorn led to serious repercussions: as a sanction, the PTAB entered adverse judgment against all challenged claim, including several claims that had otherwise survived on the merits. Id. at 51. And notably, the PTAB held that the patent owner could not avoid sanctions by pointing fingers at its counsel. Id. at 51–52.

The cases summarized in this article highlight some of the perils parties may face in relying upon test data in PTAB proceedings. Thus, it is important to develop a strategy that carefully balances such risks with the potential rewards.

[1] The Final Written Decision issued on April 18, 2024 as Paper No. 46.
[2] The PTAB also rejected petitioner’s obviousness arguments based on the same reference for at least the same reasons.
[3] § 42.65 Expert testimony; tests and data.

(a) Expert testimony that does not disclose the underlying facts or data on which the opinion is based is entitled to little or no weight. Testimony on United States patent law or patent examination practice will not be admitted.
(b) If a party relies on a technical test or data from such a test, the party must provide an affidavit explaining:

(1) Why the test or data is being used;
(2) How the test was performed and the data was generated;
(3) How the data is used to determine a value;
(4) How the test is regarded in the relevant art; and
(5) Any other information necessary for the Board to evaluate the test and data.

[4] The Final Written Decision issued as Paper No. 36 on December 19, 2023.
[5] The Final Written Decision was issued as Paper No. 58 on July 26, 2024.
[6] PGR2023-00017, Papers 22, 27.
[7] The Final Written Decision was issued as Paper No. 114 on May 22, 2023, and the Director Review Decision was issued on July 11, 2024.

This article appeared in the 2024 PTAB Year in Review: Analysis & Trends report.