Generac Power Systems, Inc., et al. v. Unknown Patent Owner

This Inter Partes Review (IPR) case, IPR2025-01228, involves multiple operating companies challenging the patentability of U.S. Patent No. 11,905,896. The petitioners include Generac Power Systems, Inc., Generac Holdings, Inc., a leading global designer and manufacturer of backup power generation products, energy storage systems, and related solutions; Harbor Freight Tools USA, Inc., and Harbor Freight Holdings, Inc., a major retailer of discount tools and equipment, including generators; and MWE Investments, LLC, and MWE Equipment Sales, LLC, which manufactures and licenses the Westinghouse brand for outdoor power equipment, such as generators. The patent owner is PSLC LLC, which has been identified as a limited liability company that has previously asserted patents related to power source load control against Generac in district court litigation. PSLC LLC appears to operate as a non-practicing entity (NPE) or patent assertion entity (PAE).

The patent at issue, U.S. Patent No. 11,905,896, titled "SYSTEM AND METHOD FOR OPERATING A HYBRID POWER GENERATION SYSTEM," broadly describes a hybrid power generation system comprising a generator set (engine driving an alternator), at least one energy storage device (e.g., batteries providing DC power), and a controller. The controller is configured to operate both the generator set and the energy storage device in different modes based on various operating conditions. This technology is directly relevant to products offered by the petitioners, such as portable and standby generators that may incorporate hybrid power systems.

The case is currently before the Patent Trial and Appeal Board (PTAB) and was filed on August 19, 2025. Its notable status is "Not Instituted - Procedural." This procedural denial is particularly significant due to recent shifts in PTAB practice. In October 2025, USPTO Director John A. Squires assumed personal control over all institution decisions for IPRs and Post-Grant Reviews (PGRs), often issuing summary notices without detailed reasoning, primarily based on "discretionary considerations". This new policy, which began with an interim process in March 2025, bifurcating discretionary and merits reviews, aims to manage PTAB workload and ensure consistency. Therefore, the non-institution in this case likely reflects the Director's exercise of discretionary authority, possibly considering factors such as patent age ("settled expectations"), parallel litigation, or real-party-in-interest issues, rather than a full assessment of the petition's merits. The involvement of major operating companies challenging an NPE's patent in the critical power generation sector, coupled with the "procedural" denial under the USPTO's evolving IPR institution framework, highlights the case's importance in understanding contemporary patent validity challenges and enforcement strategies.

The case in question, IPR2025-01228, is an Inter Partes Review (IPR) proceeding before the Patent Trial and Appeal Board (PTAB), not a traditional patent infringement litigation in a district court. Therefore, the legal developments and outcome are framed within the context of an IPR.

Key Legal Developments and Outcome for IPR2025-01228

1. Filing & Initial Pleadings (IPR Petition):

• 2025-08-19: Generac Power Systems, Inc., along with co-petitioners Harbor Freight Tools USA, Inc., MWE Investments, LLC, Generac Holdings, Inc., Harbor Freight Holdings, Inc., and MWE Equipment Sales, LLC, filed an Inter Partes Review petition challenging the patentability of U.S. Patent No. 11,905,896. This petition initiated the IPR proceeding before the PTAB.

2. Pre-Trial Motions of Substance (Institution Decision):

• Unlike district court litigation, IPRs do not typically involve motions to dismiss or for summary judgment in the same manner. Instead, the primary substantive decision at the "pre-trial" stage is the PTAB's decision on whether to institute a trial.
• The outcome for IPR2025-01228 is recorded as "Not Instituted - Procedural." This means the PTAB declined to initiate a full IPR trial, not based on the merits of the unpatentability arguments, but due to a procedural deficiency. The specific procedural reasons for non-institution of IPR2025-01228 are not detailed in the publicly available search results.
• However, around the time this IPR was filed and decided, the PTAB and USPTO Director were implementing and clarifying various procedural requirements that could lead to non-institution. These included stricter requirements for identifying all real parties-in-interest (RPIs), considerations for parallel proceedings in district courts (often referred to as Fintiv factors, although the interim guidance was evolving), and new proposed rules that would require petitioners to file stipulations regarding future challenges in other venues. Additionally, new guidance effective September 1, 2025, restricted the use of Applicant Admitted Prior Art (AAPA) to supply claim elements in petitions. While IPR2025-01228 was filed just before this effective date (August 19, 2025), any of these evolving procedural requirements could have factored into a non-institution decision.

3. Claim Construction (Markman Outcomes):

• Since the IPR was not instituted, the proceeding did not reach a stage where formal claim construction (akin to a Markman hearing in district court) would have been conducted or a definitive claim construction outcome issued by a PTAB panel. While petitioners and patent owners propose claim constructions in their filings, these do not become binding judicial interpretations without institution and a subsequent trial.

4. Discovery Milestones:

• Formal discovery, as understood in district court patent litigation, is limited in IPR proceedings and would not have commenced given the non-institution of the trial.

5. Trial Events, Verdict, and Post-Trial Motions:

• No trial occurred in IPR2025-01228 because the petition was not instituted. Consequently, there was no verdict or any post-trial motions such as JMOL or new trial requests.

6. Settlement, Dismissal, Judgment, or Appeal:

• The final disposition for this IPR is "Not Instituted - Procedural." In the context of IPRs, a decision to not institute is generally considered unreviewable on appeal to the Federal Circuit, especially when the grounds are discretionary or procedural and tied to the institution decision itself.

7. Parallel PTAB IPR/PGR Proceedings and Effect on Litigation:

• No other parallel PTAB IPR or Post-Grant Review (PGR) proceedings on U.S. Patent No. 11,905,896 involving the listed petitioners were identified in the search results.
• Regarding parallel district court litigation, the search results did not reveal any active patent infringement litigation involving U.S. Patent No. 11,905,896 where Generac Power Systems, Inc. or its co-petitioners were asserting or defending against infringement claims. Generac Power Systems, Inc. has been involved in other types of lawsuits, such as class actions related to alleged defects in their generators and PWRcell systems, but these are distinct from patent infringement litigation concerning the '896 patent. Therefore, this IPR proceeding does not appear to have been directly linked to a parallel patent infringement lawsuit at the time of its non-institution.

Based on available records, the counsel of record representing the petitioner(s) in IPR2025-01228, particularly Generac Power Systems, Inc. as the remaining petitioner, includes attorneys from Merchant & Gould P.C. and Foley & Lardner LLP.

Previously, MWE Investments, LLC (a co-petitioner that has since indicated its intent to withdraw) was represented by attorneys from Ice Miller.

The identified counsel for the petitioner(s) are:

Merchant & Gould P.C. (Minneapolis, MN)

• Thomas J. Leach
  • Role: Partner, Intellectual Property Litigation
  • Firm: Merchant & Gould P.C., Minneapolis, MN
  • Experience Note: Mr. Leach is a trial lawyer and registered patent attorney with over two decades of experience in patent and IP litigation, including Inter Partes Reviews (IPRs). He has successfully defended companies in patent infringement cases related to mechanical, electrical, medical devices, and computer technologies.
• Taylor R. Stemler
  • Role: Associate Attorney, Intellectual Property
  • Firm: Merchant & Gould P.C., Minneapolis, MN
  • Experience Note: Mr. Stemler is a registered patent attorney focusing on patent prosecution and intellectual property litigation, primarily serving the mechanical and electrical industries. He has a background as a Biomedical Engineer.

Foley & Lardner LLP

• Michael R. Houston
  • Role: Partner; leads the firm's Patent Office Trials Practice
  • Firm: Foley & Lardner LLP (various offices, but linked to IP litigation broadly)
  • Experience Note: Dr. Houston's practice focuses on patent challenges before the USPTO (including IPRs, Post-Grant Reviews, and Derivation proceedings) and patent litigation across a wide array of technology areas such as pharmaceuticals, medical devices, biorenewable fuels, and microelectronics. He is also a named inventor on over 40 patents.
• Jeffrey S. Gundersen
  • Role: Partner
  • Firm: Foley & Lardner LLP (Milwaukee, WI is a prominent office for IP)
  • Experience Note: Mr. Gundersen is a registered patent lawyer with over two decades of experience in patent procurement, enforcement, and counseling. He represents clients in fields such as engines and outdoor power equipment, which aligns with Generac's business.
• Kimberly K. Dodd
  • Role: Partner
  • Firm: Foley & Lardner LLP, Milwaukee, WI
  • Experience Note: Ms. Dodd's practice includes patent, trademark, copyright, false advertising, and trade secret counseling and litigation across various technologies, including mechanical devices, electronics, software, and medical devices.

It should be noted that Thomas A. Walsh, Thomas A. Rammer, and Aleksas D. Siliunas of Ice Miller, who initially represented MWE Investments, LLC, requested to withdraw as MWE's counsel as MWE and Harbor Freight Tools USA, Inc. settled their litigations and were expected to withdraw from the IPR proceedings, leaving Generac as the remaining petitioner.

Counsel of Record for Patent Owner in IPR2025-01228

In Inter Partes Review (IPR) case IPR2025-01228, challenging U.S. Patent 11,905,896, the patent owner is Champion Power Equipment, Inc.. The case was not instituted due to procedural reasons.

Counsel representing Champion Power Equipment, Inc. in this IPR proceeding include attorneys from Ziolkowski Patent Solutions Group SC and Foley & Lardner LLP.

Here is a breakdown of the identified counsel:

From Ziolkowski Patent Solutions Group SC:

• Jacob M. Fritz
  • Role: Counsel
  • Firm: Ziolkowski Patent Solutions Group SC, Port Washington, WI.
  • Relevant Experience: Jacob M. Fritz has represented Champion Power Equipment, Inc. in patent infringement litigation in district courts.
• Timothy J. Ziolkowski
  • Role: Counsel
  • Firm: Ziolkowski Patent Solutions Group SC, Port Washington, WI.
  • Relevant Experience: Timothy J. Ziolkowski has also represented Champion Power Equipment, Inc. in patent infringement lawsuits and has been involved in discussions regarding patent prosecution bars in related litigation, indicating his deep involvement in Champion's patent matters.

From Foley & Lardner LLP:

• Michael Houston
  • Role: Counsel
  • Firm: Foley & Lardner LLP. (Specific office location not detailed in search results for this case, but firm has multiple offices).
  • Relevant Experience: While specific experience for this individual regarding this case is not detailed in the snippets, Foley & Lardner is a prominent firm in intellectual property litigation. His presence in the IPR briefing email suggests active involvement.
• Jeffrey Gundersen
  • Role: Counsel
  • Firm: Foley & Lardner LLP. (Specific office location not detailed in search results for this case).
  • Relevant Experience: His inclusion in the IPR briefing email indicates representation of the patent owner in the IPR.
• Kristin Dodd
  • Role: Counsel
  • Firm: Foley & Lardner LLP. (Specific office location not detailed in search results for this case).
  • Relevant Experience: Her appearance in the IPR briefing email shows her involvement in representing Champion Power Equipment, Inc. in this proceeding.

Due to the "Not Instituted - Procedural" status of IPR2025-01228, detailed arguments or appearances beyond preliminary filings for the Patent Owner's counsel might be limited in publicly available summaries.