LiftWerx v. Liftra: Director Guidance on Merits for Institution

Need to know

In a rare decision offering written guidance to practitioners on the merits of an IPR challenge, Director Squires denied institution due to fundamental pleading deficiencies, including failure to map claim elements with particularity, improper reliance on examiner findings, and misapplication of prosecution silence.

In the fall of 2025, Director Squires took over review of all Patent Trial and Appeal Board (PTAB) petitions for decisions at institution and began issuing summary determinations without analysis. Since then, the Office has rarely offered written guidance on the merits of challenges in terms of meeting the reasonable likelihood standard for institution.

On July 28, 2026, Director Squires offered such guidance in an opinion issued in LiftWerx USA Inc. v. Liftra IP ApS. IPR2026-00102, Paper 18 (PTAB, July 28, 2026). In that case, the Director denied institution of inter partes review for claims 1–17 of U.S. Patent No. 12,104,578 B2 (“the ’578 patent”).

The ’578 patent covers a main shaft fixture used in the installation and repair of wind turbines, featuring “adjustable pressure mandrels with tap shoes.” LiftWerx asserted three obviousness grounds based on combinations featuring prior art references including Signore and Weaver, among other references. In its petition, LiftWerx pointed to the prosecution history of the ’578 patent and its parent (U.S. Patent No. 10,378,518), where the patent examiner had previously rejected claims involving “radially displaceable pressure mandrels with tap shoes” over Signore and Weaver.

Despite the reliance on prior findings by the Office, the Director denied institution on the merits due to fundamental pleading deficiencies.

Key failures

1. Failure to map claim elements with particularity (37 C.F.R. § 42.104(b)(4)): LiftWerx provided block quotes and colorized figures from Signore and Weaver, asserting generally that each reference “discloses pressure mandrels with tap shoes.” However, LiftWerx failed to explain why Signore’s disclosure of a “plurality of torque clamps” taught the claimed “tap shoes.” Likewise, LiftWerx highlighted a figure from Weaver without identifying which specific components represented the claimed “tap shoes.” Citing Intelligent Bio-Systems, Inc. v. Illumina Cambridge Ltd., 821 F.3d 1359, 1369 (Fed. Cir. 2016), the Director reiterated that strict adherence to the particularity requirement is of the utmost importance at the institution stage.
2. Improper reliance on examiner findings to circumvent pleading rules: LiftWerx attempted to satisfy its burden of proof by pointing to the patent examiner’s prior obviousness rejections during prosecution and noting that the applicant had not disputed those findings. The Director found references to an examiner’s prosecution findings insufficient to satisfy the affirmative requirement to explain prior art mappings under Rule 42.104(b)(4). The Director cautioned that permitting petitioners to rely on examiner findings in lieu of detailed analysis would allow petitioners to improperly circumvent petition word count limits under 37 C.F.R. § 42.24(a)(1)(i).
3. Misapplication of prosecution silence/waiver: LiftWerx suggested that the patent owner was bound by the applicant’s failure to traverse or dispute the examiner’s findings during prosecution. The Director rejected this argument, stating that patent applicants are not required to traverse every examiner finding before claims are allowed and that patent owners are not legally bound by silence during prosecution regarding non-disposed issues.

Practice tips for PTAB practitioners

1. Take care in addressing differences between language in the claims and the prior art: Practitioners should carefully consider differences between the language used in the prior art and the language used in the claims being challenged. When differences exist, the petition should explain why the different language in the prior art provides a disclosure that anticipates or renders obvious the language used in the claims. For example, if a prior art reference uses a different term than the claim (e.g., “torque clamps” vs. “tap shoes”), the petition should articulate why the disclosure of the different term meets the claim limitation or why a person of ordinary skill in the art would consider them equivalent. Petitioners should be careful to avoid equating different terms through figure annotations without offering explanations as to why equating the differently termed components is correct.
2. Prosecution rejections are not self-executing evidence: Petitioners should not assume that simply because an examiner issued a rejection during prosecution the PTAB will adopt the same prior art mappings by reference. Although pointing to examiner findings may be useful as additional evidence, the petition should provide a complete, standalone evidentiary showing for each feature of the challenged claims.
3. Avoid word count shortcuts: Petitioners should not attempt to incorporate examiner reasoning by reference to save word count. If a ground is worth asserting, it should be fully developed within the four corners of the petition under 37 C.F.R. § 42.104(b)(4).
4. Do not rely on applicant silence as acquiescence: The Office will not find that an applicant “admitted” findings in an examiner's rejection by failing to respond to them. Although noting examiner findings and the patent owner’s failure to rebut them may be permissible as additional evidence, a petitioner cannot rely on the failure to rebut and should independently demonstrate why findings consistent with the examiner’s findings are appropriate.