PTAB challenges

Proceedings overview

There is 1 AIA trial proceeding on file for US patent 11656067. This proceeding is currently active with a "Pending" status, which means the patent has not yet been challenged to a final decision. This gives a defendant a neutral defensive posture as the claims' validity is currently under examination but not yet decided.

IPR2026-00233 — Klein Tools, Inc. et al. v. Milwaukee Electric Tool Corp

• Type: Inter Partes Review
• Filed: 2026-01-26
• Status: Pending. This means the proceeding is active and has not yet reached a final decision.
• Judge panel: Information not publicly available at this stage.
• Petition grounds: The petition by Klein Tools, Inc. et al. challenged claims 1-20 of U.S. Patent No. 11,656,067 B2, alleging obviousness under 35 U.S.C. § 103 in view of various prior art combinations.
• Institution decision: The Patent Trial and Appeal Board (PTAB) instituted an inter partes review for claims 1-20 of U.S. Patent No. 11,656,067 B2 on the ground of obviousness under 35 U.S.C. § 103, based on the asserted prior art references. The institution decision was issued on July 10, 2026.
• Final Written Decision (if issued): Not yet issued as the proceeding is pending. The statutory one-year deadline for the Final Written Decision is July 10, 2027.
• Settlement / termination: Not applicable; the proceeding is active.
• Appeal: Not applicable; the proceeding is active and no Final Written Decision has been issued.
• Defensive value: The institution of IPR2026-00233 on claims 1-20 means these claims are currently being reviewed for patentability. If a demand letter cites any of these claims, their validity is uncertain and subject to potential invalidation, which could weaken an assertion built on them.

Strategic summary

All 20 claims of US patent 11656067 are currently undergoing examination in IPR2026-00233. There are no claims that have been definitively canceled or sustained through a Final Written Decision yet. Consequently, all claims (1-20) are currently untested in terms of a final PTAB judgment, although their patentability is being challenged.

Regarding the estoppel landscape, if IPR2026-00233 proceeds to a Final Written Decision, Klein Tools, Inc. et al. (and their privies) will be estopped from raising any ground they raised or reasonably could have raised against claims 1-20 in future District Court litigation or other USPTO proceedings. For a different defendant facing assertion of this patent, prior art grounds not identical to those raised in IPR2026-00233 and not reasonably discoverable by Klein Tools, Inc. et al. would theoretically still be available for a new IPR petition. However, the institution of this IPR suggests that significant prior art has been identified and deemed sufficient to warrant a trial on all claims.

The filing of this IPR by Klein Tools, Inc. et al. (and specifically mentioned by Unified Patents in the patent's litigation history) suggests a defensive aggregator or a significant competitor is challenging the patent. This is a common pattern for patents that are being asserted or are considered strategically important in the industry. The patent owner, Milwaukee Electric Tool Corp, will likely vigorously defend these claims.

Recommended next steps

• Monitor the progress of IPR2026-00233 closely via the USPTO PTAB E2E system. The institution decision was issued on July 10, 2026, meaning the Final Written Decision is due by July 10, 2027. Key milestones to watch for include expert discovery, oral hearing scheduling, and the eventual issuance of the Final Written Decision.
• Access the Institution Decision for IPR2026-00233 to understand the PTAB's reasoning for instituting the trial on claims 1-20. This decision can be found on the USPTO PTAB Decisions portal by searching for "IPR2026-00233". A defendant should carefully review the specific prior art references and obviousness arguments that the PTAB found persuasive enough to institute the trial.
• If currently being asserted against, a defendant should evaluate whether their own prior art search has yielded stronger or different invalidity arguments that could be used in a new IPR petition, considering the estoppel implications for Klein Tools, Inc. et al., but also acknowledging the PTAB's receptiveness to the obviousness arguments already presented.
• Given that the IPR was instituted on all 20 claims, consider the possibility of a stay of any co-pending district court litigation, as the validity of all asserted claims is now being considered by the PTAB.## Proceedings overview
  There is 1 AIA trial proceeding on file for US patent 11656067. This proceeding is currently active with a "Pending" status, and an institution decision has been rendered. This means the patent's claims are actively being challenged, giving a defendant a neutral-to-negative defensive posture as the claims' validity is under examination but not yet decided.

IPR2026-00233 — Klein Tools, Inc. et al. v. Milwaukee Electric Tool Corp

• Type: Inter Partes Review
• Filed: 2026-01-26
• Status: Pending. The proceeding is active, and the Patent Trial and Appeal Board (PTAB) has instituted review.
• Judge panel: Information regarding the specific Administrative Patent Judges (APJs) on the panel for IPR2026-00233 is not publicly available in the provided search results at this stage.
• Petition grounds: Klein Tools, Inc. et al. challenged claims 1-20 of U.S. Patent No. 11,656,067 B2, asserting obviousness under 35 U.S.C. § 103 based on various prior art combinations.
• Institution decision: Instituted on July 10, 2026, for claims 1-20. The PTAB determined that the petition demonstrated a reasonable likelihood that claims 1-20 of U.S. Patent No. 11,656,067 B2 are unpatentable as obvious under 35 U.S.C. § 103, based on the asserted prior art references. According to post-SAS Supreme Court precedent, if the PTAB institutes an IPR, it must issue a final written decision addressing all claims challenged by the petitioner and all grounds for unpatentability raised by the petitioner.
• Final Written Decision (if issued): Not yet issued. The statutory one-year deadline from institution for a Final Written Decision is July 10, 2027.
• Settlement / termination: Not applicable; the proceeding is active.
• Appeal: Not applicable; the proceeding is active and no Final Written Decision has been issued.
• Defensive value: The institution of IPR2026-00233 means that all 20 claims of US11656067 are now formally under review by the PTAB for obviousness. Any infringement theory relying on these claims carries increased risk, as there is a judicial finding of a "reasonable likelihood" of their unpatentability. A defendant currently facing assertion of this patent should closely monitor this IPR, as a final decision invalidating these claims could significantly impact any ongoing litigation.

Strategic summary

All 20 claims of US patent 11656067 are currently undergoing examination in IPR2026-00233, having been instituted on July 10, 2026. This means there are no claims that have been definitively canceled or sustained through a Final Written Decision yet. Consequently, all claims (1-20) are currently untested in terms of a final PTAB judgment, although their patentability is being actively challenged.

Regarding the estoppel landscape, if IPR2026-00233 proceeds to a Final Written Decision, Klein Tools, Inc. et al. (and their privies) will be estopped from raising any ground they raised or reasonably could have raised against claims 1-20 in future District Court litigation or other USPTO proceedings under 35 U.S.C. § 315(e)(2). For a different defendant facing assertion of this patent, prior-art grounds not identical to those raised in IPR2026-00233 and not reasonably discoverable by Klein Tools, Inc. et al. would theoretically still be available for a new IPR petition. However, the institution of this IPR on all claims, alleging obviousness under § 103, indicates that the PTAB found significant prior art arguments persuasive enough to proceed to trial.

The involvement of Klein Tools, Inc. et al. as the petitioner, also noted by Unified Patents, suggests a coordinated effort to challenge the patent, likely in response to assertions or as part of a broader competitive strategy. The current PTAB landscape includes new discretionary institution factors, such as domestic manufacturing presence, investment in American manufacturing operations, and small business status, that the Director may consider. However, the institution of this IPR suggests these factors did not lead to a discretionary denial in this specific case. The institution rate for IPRs has seen a downward trend, from 66-68% in fiscal years 2022-2024, to 50% in fiscal year 2025, and 37% in fiscal year 2026 year-to-date, making the institution of this IPR notable.

Recommended next steps

• Access the Institution Decision for IPR2026-00233 to understand the PTAB's detailed reasoning for instituting the trial on claims 1-20. This decision can be found on the USPTO PTAB Decisions portal by searching for "IPR2026-00233". A defendant should carefully review the specific prior art references and obviousness arguments that the PTAB found persuasive enough to institute the trial.
• Monitor the progress of IPR2026-00233 closely via the USPTO PTAB E2E system. The Final Written Decision is due by July 10, 2027.
• Given that all 20 claims are under review, a defendant in parallel district court litigation involving this patent should consider filing a motion to stay the litigation pending the outcome of the IPR. The fact that an IPR has been instituted on all challenged claims strengthens the argument for a stay.
• Evaluate the prior art used in IPR2026-00233 against any prior art you may have discovered. If your art is cumulative, a new IPR might face discretionary denial. If it presents distinct, stronger grounds not considered in IPR2026-00233, a new IPR could still be viable, but the current PTAB climate emphasizes efficiency and avoiding serial attacks.