DCT
1:19-cv-00295
Premark FEG LLC v. Champion Industries Inc
I. Executive Summary and Procedural Information
- Parties & Counsel:
- Plaintiff: Premark FEG LLC., Illinois Tool Works Inc., and ITW Food Equipment Group, LLC (Delaware / Illinois)
- Defendant: Champion Industries Inc. (North Carolina)
- Plaintiff’s Counsel: Burr Forman McNair LLP; Thompson Hine LLP
- Case Identification: Premark FEG LLC. v. Champion Industries Inc., 1:19-cv-00295, M.D.N.C., 05/22/2019
- Venue Allegations: Venue is alleged to be proper in the Middle District of North Carolina because the Defendant, Champion Industries Inc., resides within the district.
- Core Dispute: Plaintiff alleges that Defendant’s commercial warewash machines and their associated chemical sensors infringe two patents related to in-line chemical sensor devices and methods of use.
- Technical Context: The technology concerns sensors that detect the presence or absence of chemicals, such as detergents and rinse aids, in the feed lines of commercial warewashing machines to ensure proper operation.
- Key Procedural History: The complaint alleges that the dispute arose after a competitive bidding process for a major restaurant chain customer. It further alleges that a key Champion Vice President is a former employee of the Plaintiff and was aware of the Plaintiff's patent program, and that Champion was aware of Plaintiff's patents from prior litigation, which may be relevant to the allegations of willful infringement.
Case Timeline
| Date | Event |
|---|---|
| 2012-08-21 | Priority Date for ’941 and ’596 Patents |
| 2016-12-20 | ’941 Patent Issued |
| 2017-10-01 | Competitive Proposal Process Begins (approx. Q4 2017) |
| 2018-01-23 | ’596 Patent Issued |
| 2019-02-09 | Defendant Displays Accused Product at NAFEM Trade Show |
| 2019-05-22 | Complaint Filing Date |
II. Technology and Patent(s)-in-Suit Analysis
U.S. Patent No. 9,521,941 - "Warewash Machine Chemical Sensor And Related System And Method," issued December 20, 2016 (’941 Patent)
The Invention Explained
- Problem Addressed: In commercial warewashers, operators must know when chemical supply containers are empty to ensure effective cleaning. The patent notes that "accurate and responsive sensing of the chemicals is the goal" so the operator knows "precisely when the chemicals need to be replenished" (’941 Patent, col. 1:50-54).
- The Patented Solution: The patent describes a flow-through chemical sensor designed to be placed directly in a chemical feed line (’941 Patent, col. 3:5-9). The sensor features a housing with a passage for chemical flow and two opposing plate-like electrodes. Each electrode has a "unitary depression," or stamped indentation, that extends into the flow path to make direct contact with the chemical, allowing for impedance-based detection (’941 Patent, Abstract; col. 2:42-54). The specific geometry is intended to provide a reliable signal.
- Technical Importance: This in-line sensor design provides a direct measurement of chemical flow within the feed line itself, which the complaint alleges is more effective than alternative methods like measuring chemical concentration in the main wash tank (Compl. ¶22).
Key Claims at a Glance
- The complaint asserts independent claims 1 and 7 (Compl. ¶67).
- Independent Claim 1 requires a chemical sensor comprising:
- a housing having a through passage for chemical flow
- a first electrode of a plate configuration with a unitary depression that extends inward into the passage
- a second electrode of a plate configuration with a unitary depression that extends inward into the passage
- Independent Claim 7 adds further limitations to a sensor, including:
- the elements of claim 1
- a first o-ring positioned between the housing and the first electrode, secured by a fastener
- a second o-ring positioned between the housing and the second electrode, secured by a fastener
- The complaint does not explicitly reserve the right to assert dependent claims, but infringement of claims 2-5 and 8 is alleged (Compl. ¶67).
U.S. Patent No. 9,872,596 - "Warewash Machine Chemical Sensor And Related System And Method," issued January 23, 2018 (’596 Patent)
The Invention Explained
- Problem Addressed: As with its parent patent, the '596 Patent addresses the need for reliable detection of chemical presence in commercial warewashers (’596 Patent, col. 1:47-55).
- The Patented Solution: This patent claims the method of using a sensor like that described in the ’941 Patent. The method involves providing the flow-through sensor in a feed line, connecting it to a detection circuit, applying a "periodic excitation signal" (e.g., a square wave) to the circuit, and then "evaluating an output signal" to determine the presence or absence of chemical based on changes in impedance (’596 Patent, col. 7:61-col. 8:21). The patent also describes how the frequency of the excitation signal can be adjusted to optimize detection for different types of chemicals (’596 Patent, col. 6:55-63).
- Technical Importance: The claimed method provides a complete system for detection, moving beyond the physical device to the electronic process that generates a reliable result from the sensor's physical inputs.
Key Claims at a Glance
- The complaint asserts independent claims 1, 7, and 13 (Compl. ¶¶ 73, 80).
- Independent Claim 1 requires a method of detecting chemical presence by:
- providing a flow-through sensor with a housing and two electrodes having unitary depressions
- applying a periodic excitation signal to a chemical detection circuit containing the sensor
- evaluating an output signal from the circuit to determine presence or absence of chemical
- Independent Claim 7 requires a method of monitoring a chemical feed line by:
- utilizing a flow-through sensor with electrodes having plate depressions
- applying a periodic excitation signal to a circuit where the output varies according to impedance
- evaluating the output signal
- Independent Claim 13 requires a similar method of monitoring, describing the electrodes as having a "first portion that extends inward."
- The complaint also alleges infringement of dependent claims 2 and 8 (Compl. ¶¶ 73, 80).
III. The Accused Instrumentality
Product Identification
- The accused instrumentalities are Champion's "Accused Sensor," which is a chemical sensor, the warewash machines that incorporate it (the "Second Accused 5000 Model Machine" and the "Accused 6000 Model Machines"), and related replacement parts ("Accused Sensor Components") (Compl. ¶¶ 28, 31-34).
Functionality and Market Context
- The complaint alleges that Champion developed and sells the Accused Sensor for use in its commercial warewash machines to detect the presence of chemicals in the feed line (Compl. ¶¶ 28, 45). The complaint alleges that Champion's sensor includes a black housing, a through-passage for chemical flow, and two plate-like electrodes, each with an inward depression, which are sealed against the housing with o-rings (Compl. ¶¶ 40-44). A photograph provided in the complaint shows the Accused Sensor installed in a viewing window of a warewash machine (Compl. ¶28, Ex. D). The complaint alleges that the control systems in Champion's machines are designed to apply a periodic signal to the sensor circuit and evaluate the output to determine chemical presence (Compl. ¶53).
- The complaint alleges that Champion began incorporating its own sensor after first using Plaintiff's sensor to meet the demands of a "major restaurant chain customer," and that Champion competes directly with Plaintiff in the market for commercial warewash machines (Compl. ¶¶ 17, 25, 32).
IV. Analysis of Infringement Allegations
’941 Patent Infringement Allegations
| Claim Element (from Independent Claim 1) | Alleged Infringing Functionality | Complaint Citation | Patent Citation |
|---|---|---|---|
| a housing having a through passage along which chemical can flow, a sidewall of the housing having first and second openings that communicate with the through passage | The Accused Sensor includes a black housing with a passage for chemical flow and a sidewall with first and second recessed seating areas and openings. A photograph of the housing component is provided. | ¶40, ¶41, Ex. I | col. 8:1-5 |
| a first electrode mounted on the housing and aligned with the first opening, the first electrode of a plate configuration with a unitary depression that extends inward through the first opening ... such that an inwardly facing surface of the unitary depression can contact chemical flowing through the passage | The Accused Sensor's first electrode is alleged to be of a plate configuration with a unitary depression that extends inward through an o-ring and opening into the passage to contact chemical. Photographs of the electrode are provided. | ¶43, Ex. J, K | col. 8:6-14 |
| a second electrode mounted on the housing and aligned with the second opening, the second electrode of a plate configuration with a unitary depression that extends inward through the second opening ... such that an inwardly facing surface of the unitary depression can contact chemical flowing through the passage | The Accused Sensor's second electrode is alleged to be of a plate configuration with a unitary depression that extends inward through an o-ring and opening into the passage to contact chemical. The complaint describes the electrodes as being mounted on the housing at first and second seating areas aligned with openings. | ¶42, ¶44, Ex. J, K | col. 8:15-23 |
Identified Points of Contention:
- Scope Questions: The claim term "unitary depression" is highly specific. An issue may arise as to whether the shape and method of formation of the indentation in the Accused Sensor's electrodes fall within the proper construction of this term. The patent specification refers to it as an "embossment or unitary depression" formed by "a stamping operation" (’941 Patent, col. 5:32-34), which may inform the term's scope.
- Technical Questions: The complaint alleges the Accused Sensor is a copy of Plaintiff's commercial sensor (Compl. ¶63). A key question will be whether discovery reveals any subtle but legally significant differences in the material, geometry, or assembly of the Accused Sensor compared to the claimed structure.
’596 Patent Infringement Allegations
| Claim Element (from Independent Claim 1) | Alleged Infringing Functionality | Complaint Citation | Patent Citation |
|---|---|---|---|
| providing a flow through sensor in the chemical feed line, the sensor including a housing with a through passage and first and second electrodes... wherein the first electrode has a plate configuration with a first unitary depression that extends inward... wherein the second electrode has a plate configuration with a second unitary depression that extends inward... | The accused machines incorporate the "Accused Sensor" into a chemical feed line, and that sensor is alleged to have the claimed housing and electrode structure with unitary depressions, as detailed in paragraphs 40-44 of the complaint. | ¶52, ¶53 | col. 7:63-col. 8:15 |
| applying a periodic excitation signal to the chemical detection circuit | The control systems of the accused machines are alleged to be "designed to carry out a method of operation that involves applying a periodic signal to the chemical detection circuit." | ¶53 | col. 8:16-17 |
| evaluating an output signal of the chemical detection circuit to determine the presence or absence of chemical in the through passage | The control systems are alleged to be designed to evaluate the output signal, which "varies according to an impedance between the plate depressions," to determine the presence or absence of chemical. | ¶53 | col. 8:18-21 |
Identified Points of Contention:
- Scope Questions: The method claims depend on the presence of the sensor structure from the '941 patent. Therefore, the infringement analysis for the '596 patent will rise or fall with the analysis of the sensor's physical structure.
- Technical Questions: The complaint alleges the accused machines are "designed to carry out" the claimed method steps (Compl. ¶53). A central question for discovery will be how the control systems actually operate. What is the nature of the "periodic signal," and what specific algorithm or logic is used to "evaluate" the output to determine the presence of chemical?
V. Key Claim Terms for Construction
- The Term: "unitary depression" (’941 Patent, Claim 1)
- Context and Importance: This term defines the core structural innovation of the sensor's electrodes. The infringement analysis for the apparatus claims of the ’941 Patent, and consequently the method claims of the ’596 Patent, depends heavily on whether the accused electrodes possess this feature. Practitioners may focus on this term because it is a specific, non-standard descriptor that appears intended to distinguish the invention from prior art.
- Intrinsic Evidence for Interpretation:
- Evidence for a Broader Interpretation: The specification suggests some flexibility, describing the feature as an "embossment or unitary depression" that can be formed by "a stamping operation" (’941 Patent, col. 5:32-34). This language could support a construction that covers a range of stamped or formed indentations, not just a single shape.
- Evidence for a Narrower Interpretation: The patent figures, such as Figure 2B, depict a very specific, smooth, concave depression. A defendant could argue that the term should be limited to the shape and profile shown in these specific embodiments. The use of "unitary" also suggests the depression must be formed from the same single piece of material as the electrode plate itself, precluding a multi-part construction.
VI. Other Allegations
- Indirect Infringement: The complaint alleges induced infringement of the ’596 Patent under 35 U.S.C. § 271(b). The basis is the allegation that Champion sells machines to customers (like MRCC) that are "specifically designed to carry out the claimed methods" of the ’596 Patent, and by doing so with knowledge of the patent, Champion induces its customers to directly infringe (Compl. ¶82).
- Willful Infringement: The complaint alleges willful infringement of both patents. The allegations are based on purported pre-suit knowledge. Specifically, the complaint alleges that Champion's VP of New Business & Product Development is a former Product Line Manager from Plaintiff's company and was aware of its patenting practices (Compl. ¶¶ 57-59). It also alleges that Champion was aware from "prior litigation" that Plaintiff's parent company holds patents on its innovations and that Champion intentionally copied the design of Plaintiff's commercial sensor (Compl. ¶¶ 60, 69).
VII. Analyst’s Conclusion: Key Questions for the Case
- A central issue will be one of intent and evidence of copying: the complaint makes strong allegations of willful infringement based on a former employee's knowledge and intentional copying. A key question will be whether discovery supports these allegations, which could significantly impact potential damages.
- The case will also turn on a question of structural identity: does the accused sensor’s electrode design, particularly the indentation, fall within the scope of the claim term "unitary depression"? The resolution of this claim construction issue will likely be dispositive for the infringement analysis of the ’941 Patent.
- Finally, a key evidentiary question will be one of operational equivalence: for the ’596 method patent, the case will depend on what discovery reveals about the specific electronic operations of the accused machines. Does the signal processing logic used by Champion's controllers perform the same steps as those required by the method claims, or is there a fundamental mismatch in technical operation?