DCT
8:26-cv-02005
Premier Filters Inc v. TSS USA LLC
Key Events
Complaint
Table of Contents
complaint Intelligence
I. Executive Summary and Procedural Information
- Parties & Counsel:
- Plaintiff: Premier Filters, Inc. (California)
- Defendant: TSS USA, LLC d/b/a TSS USA MANUFACTURING (Pennsylvania)
- Plaintiff's Counsel: Knobbe, Martens, Olson & Bear, LLP
- Case Identification: 8:26-cv-02005, C.D. Cal., 07/24/2026
- Venue Allegations: Venue is alleged to be proper as the Plaintiff, Premier Filters, is located within the district, a substantial part of the events giving rise to the claims occurred in the district, and the Defendant is allegedly subject to personal jurisdiction there.
- Core Dispute: Plaintiff seeks a declaratory judgment that its High-Altitude Electromagnetic Pulse (HEMP) filters do not infringe Defendant's patent, following Defendant's assertions of infringement and threats of litigation.
- Technical Context: The technology concerns specialized electrical filters designed to protect sensitive electronic equipment and critical infrastructure from the damaging effects of an electromagnetic pulse.
- Key Procedural History: The dispute arises from a soured business relationship where Plaintiff Premier Filters was the manufacturer for Defendant TSS. An inventor of the patent-in-suit, Kenneth Ogden, reportedly joined Premier Filters after the relationship between the parties began. The patent was assigned to TSS. Following the termination of their supplier agreement, TSS allegedly accused Premier Filters of infringement and demanded the return of purported trade secrets, creating the controversy underlying this declaratory judgment action.
Case Timeline
| Date | Event |
|---|---|
| 2018-01-23 | Provisional Application No. 62/620,522 Priority Date |
| 2019-01-22 | '918 Patent Application Filing Date |
| 2019-02-07 | Inventor Kenneth Ogden assigns interest in the patent application to TSS |
| 2019-02-15 | Premier Filters is formed |
| 2019-07-25 | '918 Patent application is published |
| 2021-08-24 | U.S. Patent No. 11,102,918 Issues |
| 2025-07-18 | Premier Filters sends letter to TSS to end supplier relationship |
| 2025-10-17 | TSS responds to Premier Filters, declining a covenant not to sue |
| 2025-11-11 | Premier Filters responds to TSS's October letter |
| 2026-01-21 | TSS replies to Premier Filters, stating intent to "vigorously enforce its rights" |
| 2026-05-29 | Premier Filters sends letter to TSS regarding alleged false marking of products |
| 2026-06-05 | TSS asserts in response that its records "indicate that all HEMP filters are covered by the '918 Patent" |
| 2026-07-24 | Complaint for Declaratory Judgment is filed |
II. Technology and Patent(s)-in-Suit Analysis
U.S. Patent No. 11,102,918 - Electromagnetic pulse/high altitude electromagnetic pulse (EMP/HEMP) filter system
- Patent Identification: U.S. Patent No. 11,102,918, "Electromagnetic pulse/high altitude electromagnetic pulse (EMP/HEMP) filter system," issued August 24, 2021.
The Invention Explained
- Problem Addressed: The patent addresses the problem of catastrophic failures, including explosions, in previous medium-voltage (600V to 69kV) HEMP filters, which did not meet necessary reliability levels ('918 Patent, col. 2:17-24). Existing designs were also susceptible to failure from line harmonics, separate from the EMP threat ('918 Patent, col. 2:52-54).
- The Patented Solution: The invention is a filter system designed for medium voltage applications (1000 to 5000 volts) that avoids using oil-filled components to preclude explosions ('918 Patent, abstract; '918 Patent, col. 2:34-38). The patented design features a housing assembly comprising a "backing plate" that provides structural support for the filter elements and end compartments ('918 Patent, col. 5:28-32; '918 Patent, FIG. 3). This modular construction, with distinct input, central, and output compartments, is designed to isolate the filter components and provide robust shielding ('918 Patent, col. 5:18-25).
- Technical Importance: The solution purports to provide a more reliable and safer HEMP filter for medium-voltage applications by using oil-free components and a design resistant to both EMP and line harmonics, which was a noted failure point in prior art systems ('918 Patent, col. 2:48-54).
Key Claims at a Glance
- The complaint seeks a declaratory judgment of non-infringement of the '918 Patent, implicating all claims ('918 Patent, PRAYER FOR RELIEF ¶A). The non-infringement argument focuses on a limitation present in both independent claims 1 and 10 ('918 Patent, ¶33).
- Independent Claim 1 requires:
- a housing assembly comprising:
- a backing plate;
- an input compartment, mechanically coupled to said backing plate;
- a plurality of filter elements, each mechanically coupled to said backing plate and having input and output connections;
- an output compartment, mechanically coupled to said backing plate.
- Independent Claim 10 is structurally similar to claim 1, additionally requiring that the input connection includes a first busbar connector with a surge arrestor and the output connection includes a second busbar connector.
- The complaint does not explicitly reserve the right to address dependent claims, but seeks a judgment of non-infringement of "any claim of the '918 Patent" ('918 Patent, ¶34).
III. The Accused Instrumentality
Product Identification
- The "Products at Issue" are a "new line of HEMP filters" that Premier Filters has designed and now offers for sale in the United States after ending its supplier agreement with TSS (Compl. ¶27; Compl. ¶31). These products are listed in Exhibit D to the complaint (Compl. ¶31).
Functionality and Market Context
- The complaint describes the Products at Issue as HEMP filters, placing them in the same technical and market space as the products sold by TSS (Compl. ¶¶11-12; Compl. ¶27). Premier Filters alleges that these new products are in some cases "substantially identical, in relevant part, to corresponding HEMP filters that TSS has asserted are covered by the '918 Patent" but for the absence of a key claimed feature (Compl. ¶28; Compl. ¶31). The filing of the declaratory judgment action itself suggests that Premier Filters views the products as commercially significant and wishes to clear a path to market without the threat of litigation from TSS (Compl. ¶¶5-6).
No probative visual evidence provided in complaint.
IV. Analysis of Infringement Allegations
The complaint seeks a declaratory judgment of non-infringement. The core allegation is that the Plaintiff's (Premier Filters) products are missing a required element of the patent's claims.
'918 Patent Infringement Allegations
| Claim Element (from Independent Claim 1) | Alleged Infringing Functionality | Complaint Citation | Patent Citation |
|---|---|---|---|
| a housing assembly comprising: a backing plate; | The complaint alleges that "all of the Products at Issue do not include 'a backing plate' as required by both independent claims 1 and 10." | ¶33 | col. 8:53 |
| an input compartment, mechanically coupled to said backing plate | As the products allegedly lack a "backing plate," they consequently do not include an input compartment "mechanically coupled to said backing plate." | ¶¶33, 11:26-27 | col. 8:54-55 |
| a plurality of filter elements, each ... mechanically coupled to said backing plate | As the products allegedly lack a "backing plate," they consequently do not include filter elements "mechanically coupled to said backing plate." | ¶¶33, 11:27-28 | col. 8:58-63 |
| an output compartment, mechanically coupled to said backing plate | As the products allegedly lack a "backing plate," they consequently do not include an output compartment "mechanically coupled to said backing plate." | ¶¶33, 12:1 | col. 9:1-3 |
Identified Points of Contention
- Scope Questions: The central dispute hinges on the definition of "backing plate." The complaint's theory of non-infringement rests entirely on the assertion that its products lack this specific component (Compl. ¶33). The case will question whether the term "backing plate" requires a distinct, separate component as arguably depicted in the patent's figures, or if its functions could be met by an integrated part of a filter housing.
- Technical Questions: A factual question will be whether the accused products contain any structure that performs the role of the claimed "backing plate," even if not explicitly named as such. The patent describes the backing plate as providing "support for the two end caps or compartments 12, 18 and the three or four filter elements 16" ('918 Patent, col. 5:28-32). The court will need to examine the structure of the Premier Filters products to determine if a corresponding support structure exists.
V. Key Claim Terms for Construction
- The Term: "a backing plate"
- Context and Importance: This term is the lynchpin of Premier Filters' non-infringement case. It appears in both independent claims 1 and 10, and its absence in the accused products is the sole basis for non-infringement articulated in the complaint (Compl. ¶33). The entire patent case may be decided on the construction of this term and its application to the accused products. Practitioners may focus on this term because its presence is a prerequisite for infringement of all asserted claims.
- Intrinsic Evidence for Interpretation:
- Evidence for a Broader Interpretation: The claims require the housing assembly to comprise a backing plate, which is open-ended language. A party could argue that any structural element of the housing that provides the requisite support for the other components meets the definition, even if it is not a discrete, flat plate. The specification does not appear to explicitly define the term, potentially leaving it open to its plain and ordinary meaning in the context of mechanical assemblies.
- Evidence for a Narrower Interpretation: The patent specification consistently refers to the "backing plate" as a distinct element (element 22 in FIG. 3) that "provides the support for the two end caps or compartments... and the... filter elements" ('918 Patent, col. 5:28-32). The claims require the input compartment, output compartment, and filter elements to all be "mechanically coupled to said backing plate" (e.g., '918 Patent, claim 1), suggesting it is a central, unifying structural member. A party could argue that this consistent description and functional relationship limits the term to a structure that mirrors element 22, and not merely an integrated wall of a unitary housing.
VI. Other Allegations
- Indirect Infringement: This is a declaratory judgment action for non-infringement, so there are no allegations of indirect infringement by the plaintiff.
- Willful Infringement: The complaint does not allege willfulness. However, it establishes the existence of a controversy by citing TSS's threats to pursue litigation for "willful infringement and treble damages" against Premier Filters (Compl. ¶4; Compl. ¶21). This allegation of pre-suit knowledge and threats from the patentee (TSS) is the basis for Premier Filters' "reasonable apprehension of suit" required for a declaratory judgment action (Compl. ¶28).
VII. Analyst's Conclusion: Key Questions for the Case
This declaratory judgment action appears to center on a single, dispositive issue of claim construction and its application. The key questions for the court will likely be:
- A core issue will be one of definitional scope: What is the proper construction of the term "backing plate" as used in the '918 Patent? Is it limited to the discrete structural component shown in the patent's embodiments, or can it be construed more broadly to cover any part of a housing that provides support for the filter's internal components?
- A key evidentiary question will be one of structural presence: Assuming a definition for "backing plate" is established, do Premier Filters' "Products at Issue" contain a structure that meets that definition, either literally or as an equivalent? The case will likely turn on a comparison of the accused product designs against the language of the claims.
- An underlying issue is the interplay with trade secrets: The complaint interweaves the patent dispute with a parallel dispute over alleged trade secrets related to the same technology (Compl. ¶¶2-4). While the patent non-infringement analysis is distinct, the shared history and technology may influence the broader legal strategy and potential outcomes of the overall litigation between the parties.
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