DCT
2:23-cv-02717
Harcosemco LLC v. Herber Aircraft Service Inc
Key Events
Amended Complaint
I. Executive Summary and Procedural Information
- Parties & Counsel:
- Plaintiff: HarcoSemco LLC (Connecticut)
- Defendant: Herber Aircraft Service Inc. (California)
- Plaintiff’s Counsel: Rutan & Tucker, LLP; Calfee, Halter & Griswold LLP
- Case Identification: 2:23-cv-02717, C.D. Cal., 05/24/2023
- Venue Allegations: Venue is asserted based on Defendant being a California corporation with its principal place of business within the Central District of California, where it allegedly committed acts of infringement and maintains regular and established places of business.
- Core Dispute: Plaintiff alleges that Defendant’s aircraft engine thermocouple harnesses infringe a patent related to optimizing wire harness configurations to balance electrical resistance without requiring equal wire lengths.
- Technical Context: Thermocouple harnesses are critical for monitoring jet engine temperatures, where balancing electrical resistance across multiple sensors is essential for obtaining accurate average temperature readings for safety and efficiency.
- Key Procedural History: The complaint alleges that Defendant obtained a Federal Aviation Administration (FAA) Parts Manufacturer Approval (PMA) for the accused product, identifying it as a replacement for Plaintiff's product. Plaintiff also alleges it provided Defendant with a copy of the patent-in-suit prior to filing the complaint.
Case Timeline
| Date | Event |
|---|---|
| 2016-02-24 | U.S. Patent No. 11,525,741 Priority Date |
| 2020-03-26 | Defendant obtains FAA PMA for Accused Harness |
| 2022-12-13 | U.S. Patent No. 11,525,741 Issue Date |
| 2023-02-24 | Plaintiff’s counsel sends '741 Patent to Defendant’s counsel |
| 2023-05-24 | First Amended Complaint Filing Date |
II. Technology and Patent(s)-in-Suit Analysis
U.S. Patent No. 11,525,741 - "Optimized Thermocouple System and Method"
- Patent Identification: U.S. Patent No. 11,525,741, "Optimized Thermocouple System and Method," issued December 13, 2022 (’971 Patent).
The Invention Explained
- Problem Addressed: In multi-sensor thermocouple systems for jet engines, achieving an accurate average temperature reading requires that the electrical resistance of the wiring for each sensor (each "channel") be balanced. The patent states that the conventional method for balancing resistance is to make the wires for each channel equal in length, often requiring cumbersome "looped back" wires for sensors closer to the central junction box, which adds unnecessary weight, cost, and complexity (’971 Patent, col. 8:33-65).
- The Patented Solution: The invention claims a thermocouple harness that achieves balanced resistance without requiring equal wire lengths. It does this by leveraging the different intrinsic resistivity of the two types of metal wires (e.g., Chromel and Alumel) used in a thermocouple. By using specific, unequal lengths of the positive and negative wire legs, the system is configured to balance the total series resistance for each channel, thereby eliminating the need for extra "looped back" wiring and reducing overall weight (’971 Patent, col. 2:5-14; Figs. 17-18).
- Technical Importance: This approach allows for the design of lighter, less bulky, and more cost-effective thermocouple harnesses, which provides a significant advantage in the weight-sensitive aerospace industry (’971 Patent, col. 2:11-14).
Key Claims at a Glance
- The complaint asserts independent claims 1 and 18, and dependent claim 19 (’971 Patent, Compl. ¶21). The infringement analysis focuses on claim 19, which depends from claim 18.
- Independent Claim 18: The core elements of this apparatus claim are:
- A thermocouple wire harness comprising at least two first wire legs of a first material and at least two second wire legs of a second, different-resistivity material.
- A structural requirement that the total wire length of at least one of the second wire legs is greater than the total wire length of each of the first wire legs.
- A structural requirement that the total wire length of at least one of the first wire legs is shorter than the total wire length of each of the second wire legs.
- A functional requirement that "the lengths of the wire legs are configured to balance series resistance between the thermocouples."
- The complaint reserves the right to assert additional claims.
III. The Accused Instrumentality
Product Identification
The Herber Gas Temperature (EGT) Thermocouple Wiring Harness Assembly, Part Number 2A4524HAS (the “Accused Harness”) (Compl. ¶12).
Functionality and Market Context
The Accused Harness is a component used for temperature monitoring in aircraft engines (Compl. ¶12). The complaint includes an image showing the physical assembly of the Accused Harness (Compl. ¶12, Fig. 1). According to the complaint, Defendant obtained an FAA PMA for the Accused Harness which specifically identifies it as an approved replacement part for Plaintiff’s product number 30558-000 (Compl. ¶13). The complaint provides a screenshot of the FAA’s database entry for this PMA (Compl. ¶13, Fig. 2).
IV. Analysis of Infringement Allegations
The complaint references a claim chart in Exhibit 3A, which was not publicly filed with the complaint; the following analysis is based on the narrative allegations. (Compl. ¶23). The complaint quotes the language of claim 19 and alleges that the Accused Harness is "configured exactly as recited" therein (Compl. ¶¶22-23).
’971 Patent Infringement Allegations
| Claim Element (from Independent Claim 18, via dependent Claim 19) | Alleged Infringing Functionality | Complaint Citation | Patent Citation |
|---|---|---|---|
| a thermocouple wire harness comprising: at least two first wire legs of a first material having a first resistivity... | The Accused Harness is a thermocouple wire harness. | ¶20 | col. 19:4-9 |
| at least two second wire legs of a second material having a second resistivity different than the first resistivity... | The Accused Harness is designed for connection to thermocouples and comprises thermocouple wire legs. | ¶23 | col. 19:10-14 |
| wherein the total wire length of at least one of the second wire legs is greater than the total wire length of each of the at least two first wire legs, | The complaint alleges the Accused Harness has this specific relative wire length configuration. | ¶¶22-23 | col. 19:15-18 |
| wherein the total wire length of at least one of the first wire legs is shorter than the total wire length of each of the at least two second wire legs... | The complaint alleges the Accused Harness has this specific relative wire length configuration. | ¶¶22-23 | col. 19:19-22 |
| wherein the lengths of the wire legs are configured to balance series resistance between the thermocouples. | The complaint alleges the Accused Harness is configured as recited in the claim. | ¶23 | col. 19:23-25 |
Identified Points of Contention
- Technical Questions: A central issue will be factual and evidentiary. What are the actual, measured lengths and material types of the various wire legs in the Accused Harness? The complaint alleges the harness meets the specific structural ratios of the claims but does not provide the underlying data (e.g., from reverse engineering or testing) to support this conclusion.
- Scope Questions: What level of intent or design purpose is required by the claim limitation "configured to balance series resistance"? The defense may argue that the physical structure of the Accused Harness was dictated by other design constraints and that any resulting resistance balance is incidental, not the result of the configuration claimed in the patent.
V. Key Claim Terms for Construction
- The Term: "configured to balance series resistance"
- Context and Importance: This term adds a functional aspect to an otherwise structural claim. The infringement analysis may depend on whether this requires proof of a specific design intent to use unequal wire lengths for resistance balancing, or if it is met simply by a structure that achieves the result. Practitioners may focus on this term to dispute whether the Accused Harness was intentionally designed in the manner taught by the patent.
- Intrinsic Evidence for Interpretation:
- Evidence for a Broader Interpretation: The patent’s summary broadly states that the "invention utilizes a scientific model to analyze... and take advantage of the systems' degrees of freedom to optimize designs" for balancing resistance, which could support interpreting "configured to" as encompassing any structure that achieves this optimized outcome (’971 Patent, col. 2:8-12).
- Evidence for a Narrower Interpretation: The detailed description and Figure 21 outline a specific, multi-step optimization method. This could support an argument that "configured to" requires an intentional implementation of such a design process, not merely an incidental outcome (’971 Patent, Fig. 21; col. 15:21-41).
VI. Other Allegations
- Willful Infringement: The complaint alleges that Defendant’s infringement has been willful, asserting that Defendant had knowledge of the ’971 Patent (Compl. ¶25). The basis for this knowledge includes correspondence between counsel after the patent issued and, specifically, a letter dated February 24, 2023, where Plaintiff’s counsel allegedly sent a copy of the ’971 Patent to Defendant’s counsel (Compl. ¶¶15, 26).
VII. Analyst’s Conclusion: Key Questions for the Case
- A primary issue for the court will be one of factual evidence: Does a physical analysis of the Accused Harness reveal that it is actually built with the specific, unequal wire-length relationships between its different conductive materials as structurally recited in the asserted claims? The case’s outcome may depend heavily on the results of product teardowns and measurements.
- A second core issue will be one of claim construction: Can the phrase “configured to balance series resistance” be met by any harness that incidentally achieves a balanced state, or must the plaintiff prove that the harness was intentionally designed according to the optimization principles taught in the patent?