Comarco Wireless Systems v. Panasonic: Charging Patent Suit Dismissed With Prejudice
Comarco Wireless Systems LLC filed a patent infringement action against Panasonic Corp. in the Eastern District of Texas, asserting three patents covering charging technology against Panasonic’s Toughbook and LUMIX product lines. The case resolved in just 106 days when Comarco voluntarily dismissed with prejudice — permanently closing all claims.
A three-patent charging IP dispute resolved before discovery even began
On April 21, 2025, Comarco Wireless Systems LLC filed suit against Panasonic Corp. in the U.S. District Court for the Eastern District of Texas, asserting infringement of three patents — US10855087B1, US10951042B2, and US9413187B2 — all directed to charging technology. The accused products spanned Panasonic’s commercial and consumer hardware portfolios, including the Toughbook 33, 55, G2, and S1 rugged laptop chargers, as well as the DC-GH7, DC-GH8, DCS5M2, and LUMIX S1R/S1 camera chargers.
The case closed on August 5, 2025, just 106 days after filing, when Comarco filed Notices of Dismissal representing that both the lead case and member case were voluntarily dismissed with prejudice. The Eastern District of Texas accepted and acknowledged the dismissals pursuant to Rule 41(a)(1)(A)(i), formally dismissing all claims with prejudice and denying all pending relief as moot. Each party was ordered to bear its own costs, expenses, and attorneys’ fees — suggesting no negotiated cost-sharing was reflected in the public record.
The speed of resolution — 106 days with no reported claim construction, Markman hearing, or discovery schedule — suggests the parties reached an agreement, or Comarco made a strategic decision to withdraw, well before substantive litigation began. The with-prejudice designation is significant: Comarco cannot reassert these same claims against Panasonic on these patents in the future. What drove the early exit — whether settlement, licensing, or a commercial decision — is not disclosed in the public record.
Filing to Dismissed with Prejudice in 106 days
106 days — resolved well before the typical 2–3 year E.D. Tex. patent trial cycle
Dismissed with prejudice: what Comarco’s withdrawal means for both parties
Rule 41 dismissal with prejudice: the point of no return
Under Rule 41(a)(1)(A)(i), a plaintiff may voluntarily dismiss before the opposing party serves an answer or motion for summary judgment. When filed with prejudice, as here, it operates as a final adjudication on the merits. The court accepted Comarco’s notices and formally closed all claims — meaning no second bite at the apple on these patents against Panasonic.
Rule 41(a)(1)(A)(i) — voluntary, with prejudiceComarco permanently surrenders its claims against Panasonic
A with-prejudice dismissal is a permanent bar: Comarco cannot refile these infringement claims — based on US10855087B1, US10951042B2, or US9413187B2 — against Panasonic for the same accused products. Whether this reflects a licensing resolution, a commercial decision, or a reassessment of claim strength is not disclosed. Comarco retains the patents and may enforce them against other parties.
Claims barred — no refiling against PanasonicPanasonic exits without a merits ruling — but faces no res judicata shield elsewhere
Panasonic secures a clean exit: all claims dismissed with prejudice and no cost award against it. The court’s order denying pending relief as moot means no injunction risk remains on these products. However, the dismissal does not adjudicate the validity or scope of Comarco’s patents — those remain in force and could be asserted against other charging product manufacturers.
Clean exit — no merits adjudicationCharging IP remains live — Comarco’s patents are still enforceable against the market
The three Comarco patents survive this litigation untouched. Competitors in the ruggedised laptop and camera charger space — particularly those making products functionally similar to the Toughbook or LUMIX charger lines — should note that Comarco retains active enforcement rights. The early dismissal provides no claim construction record or validity guidance, leaving the patent scope legally uncertain for the broader market.
Patents survive — market risk remainsFull party and counsel information
| Role | Name | Type | Detail |
|---|---|---|---|
| Plaintiff | Comarco Wireless Systems, LLC | Company | Wireless charging IP licensor — holder of US10855087B1, US10951042B2, and US9413187B2Search in Eureka ↗ |
| Defendant | Panasonic, Corp. | Company | Panasonic Corp. — global electronics manufacturer, maker of Toughbook and LUMIX product linesSearch in Eureka ↗ |
| Plaintiff counsel | David R. Bennett | Attorney | Counsel for Comarco Wireless Systems, LLCSearch in Eureka ↗ |
| Plaintiff counsel | Steven Kalberg | Attorney | Counsel for Comarco Wireless Systems, LLCSearch in Eureka ↗ |
| Defendant counsel | Joshua David Sibble | Attorney | Counsel for Panasonic, Corp.Search in Eureka ↗ |
| Defendant law firm | Panasonic Intellectual Property Corporation Of America | Law Firm | Representing Panasonic, Corp.Search in Eureka ↗ |
| Presiding judge | Judge N/A | Judge | Texas Eastern District CourtSearch in Eureka ↗ |
Official order — verbatim text
The court’s order is unambiguous: both the lead and member cases are dismissed with prejudice under Rule 41(a)(1)(A)(i), meaning Comarco itself initiated the exit before Panasonic filed any responsive pleading. The ‘each party bears its own costs’ language is a standard feature of pre-answer voluntary dismissals and does not imply a finding on the merits. Critically, no claim construction, validity ruling, or infringement finding was issued — the three asserted patents remain in force and uninterpreted by any court.
US10855087B1, US10951042B2 & US9413187B2 — DC charging technology patents
The three asserted patents — US10855087B1 (application US16/991295), US10951042B2 (application US17/077699), and US9413187B2 (application US13/943453) — cover charging technology applicable to a range of portable electronic devices. The application numbers span multiple filing generations, suggesting Comarco has built a layered patent portfolio in this domain over time. The accused products include both ruggedised commercial hardware (Toughbook series) and consumer imaging equipment (LUMIX and DC-series camera chargers), indicating the patents are drafted broadly enough to span distinct product categories.
For the charging hardware sector, Comarco’s portfolio presents a meaningful enforcement risk. The breadth of accused SKUs — eight distinct charger models across two product families — suggests the patents may cover fundamental charging circuit or power delivery architectures rather than narrow implementation details. No claim construction record exists from this litigation, which means competitors cannot rely on any court-narrowed interpretation of the claims. Manufacturers of DC chargers for laptops, ruggedised devices, or interchangeable-lens cameras should treat these patents as active risk assets pending any post-grant or inter partes review proceedings.
Should your team run an FTO against US10855087B1, US10951042B2 & US9413187B2?
Any company designing or selling DC chargers for ruggedised laptops, tablets, or mirrorless cameras — particularly those whose products share functional architecture with Panasonic’s Toughbook or LUMIX charger lines — should assess freedom to operate against these three Comarco patents. The with-prejudice dismissal means no claim construction guidance exists, leaving the patent boundaries undefined. The broader the product overlap with the accused Panasonic SKUs, the more urgent the FTO assessment.
PatSnap Eureka’s FTO Search Agent can map the claim scope of US10855087B1, US10951042B2, and US9413187B2 against your product’s charging architecture, identify prior art that may constrain the claims, and flag any continuation or divisional applications in Comarco’s portfolio that could extend risk. With no court-narrowed claims on record, a proactive FTO review is the most reliable way to assess and manage exposure before any enforcement action is filed.
Run a freedom-to-operate analysis on US10855087B1 to assess your product’s exposure
Run FTO in Eureka →Similar charging technology patent cases in E.D. Texas and federal courts
Cases involving DC charging and power delivery patents litigated in the Eastern District of Texas and comparable federal venues, including NPE-driven enforcement actions.
What this case signals for the charging technology IP landscape
A 106-day with-prejudice exit in E.D. Tex. typically signals swift resolution — but leaves market-wide patent risk intact.
With-prejudice exits in E.D. Tex. often follow rapid licensing negotiations
When a plaintiff dismisses with prejudice this quickly — before any Markman ruling or discovery — it consistently suggests either a licensing deal was reached or a strategic withdrawal was made. The no-costs order is consistent with a clean commercial exit rather than a defeat on the merits. IP teams monitoring Comarco’s enforcement activity should note this pattern.
Comarco’s three charging patents remain live enforcement tools for the broader market
US10855087B1, US10951042B2, and US9413187B2 received no validity or claim-scope adjudication in this case. Any manufacturer of DC chargers for ruggedised laptops or mirrorless cameras whose products share functional similarities with the accused Panasonic SKUs should assess exposure. The absence of a claim construction record makes FTO analysis more — not less — important.
Comarco v Panasonic — key questions answered
The public record does not disclose Comarco’s reason for the voluntary dismissal with prejudice. The case closed 106 days after filing, before any Markman hearing or discovery, which is consistent with a licensing resolution or strategic commercial decision. A with-prejudice designation permanently bars Comarco from refiling the same claims against Panasonic on these patents.
Panasonic is protected from any future infringement claims by Comarco based on US10855087B1, US10951042B2, and US9413187B2 for the accused charger products. The dismissal with prejudice operates as a final adjudication, preventing re-litigation of these claims. However, it does not address the validity or scope of the patents, which remain enforceable against other parties.
Yes. A voluntary dismissal with prejudice does not affect patent validity or enforceability against third parties. US10855087B1, US10951042B2, and US9413187B2 remain active issued patents. Comarco retains the right to assert them against other manufacturers of DC charging products whose devices fall within the patent claims.
The case was filed in the U.S. District Court for the Eastern District of Texas, a historically plaintiff-friendly venue for patent litigation known for fast case scheduling and experienced patent judges. The early voluntary dismissal means the court’s procedural environment was never fully tested in this dispute.
Eight Panasonic charger models were accused: DC-GH7, DC-GH8, DCS5M2, LUMIX S1R/S1 chargers in the consumer camera segment, and Toughbook 33, Toughbook 55, Toughbook G2, and Toughbook S1 chargers in the ruggedised commercial laptop segment. The breadth of accused products across two distinct hardware families suggests the asserted patents cover a general charging architecture.
PatSnap Eureka searches patents and litigation data to answer instantly.