DCT
3:17-cv-00042
LB White Co Inc v. GSI Group LLC
I. Executive Summary and Procedural Information
- Parties & Counsel:
- Plaintiff: L.B. White Company, Inc. (Wisconsin)
- Defendant: GSI Group LLC (Delaware)
- Plaintiff’s Counsel: DeWitt Ross & Stevens s.c.
- Case Identification: 3:17-cv-00042, W.D. Wis., 06/01/2017
- Venue Allegations: Plaintiff alleges venue is proper based on Defendant’s regular and systematic business activities, distribution of products, and commission of infringing acts within the Western District of Wisconsin.
- Core Dispute: Plaintiff alleges that Defendant’s VariFlame line of variable rate heating systems, used in agricultural settings, infringes a patent related to technology for precise temperature control.
- Technical Context: The technology concerns advanced environmental control systems for animal confinement buildings, where precise temperature management can improve energy efficiency and animal health.
- Key Procedural History: The operative filing is an Amended Complaint, though no other significant procedural events, such as prior litigation or administrative proceedings involving the patent, are mentioned.
Case Timeline
| Date | Event |
|---|---|
| 2011-06-07 | U.S. Patent No. 9,328,937 Priority Date |
| 2016-05-03 | U.S. Patent No. 9,328,937 Issued |
| 2017-06-01 | Amended Complaint Filed |
II. Technology and Patent(s)-in-Suit Analysis
U.S. Patent No. 9,328,937 - "Variable Rate Heating for Agricultural Purposes"
- Patent Identification: U.S. Patent No. 9,328,937, "Variable Rate Heating for Agricultural Purposes", issued May 3, 2016.
The Invention Explained
- Problem Addressed: The patent describes conventional heating control in agricultural buildings as a simple "on" or "off" switch, which results in significant temperature swings ("overshoot and undershoot") ('937 Patent, col. 1:29-32). This "Drift" is inefficient, wastes fuel, and can cause stress to animals by creating an inconsistent environment ('937 Patent, col. 2:48-54).
- The Patented Solution: The invention proposes a "variable rate" heating system that modulates its output to maintain a highly stable temperature. Instead of a simple on/off switch, it employs a controller with a more sophisticated logic, described as a Proportional-plus-Integral (PI) algorithm, to calculate an "error correction" based on both the current temperature deviation and past temperature deviations ('937 Patent, col. 8:4-11, Abstract). This allows the system to make fine adjustments and "lock" onto a desired setpoint temperature within a narrow "dead-band" ('937 Patent, col. 10:5-10).
- Technical Importance: By eliminating large temperature variations, the technology aims to reduce energy consumption and improve animal productivity in sensitive agricultural settings like swine facilities ('937 Patent, col. 5:41-48).
Key Claims at a Glance
- The complaint asserts infringement of at least independent Claim 1 ('Compl. ¶¶ 15, 26).
- The essential elements of independent Claim 1 include:
- A temperature control system with a variable rate heater, a temperature sensor, and a controller.
- The controller accepts a user-defined "heat set point temperature."
- The controller determines the difference between the set point and the measured current temperature.
- If the difference is within a "dead-band value," the heat output remains unchanged.
- If the difference exceeds the dead-band, the controller determines an "error correction based on both the difference and on one or more past error corrections."
- The controller then sets an "adjusted heat output based on the error correction."
- A "timeout" feature turns the heater off if it runs at its minimum output for a set period.
III. The Accused Instrumentality
Product Identification
- The "VariFlame" variable rate heating system, manufactured by Automated Production Systems ("APS"), a division of Defendant GSI (Compl. ¶13).
Functionality and Market Context
- The VariFlame is described as a temperature control system for animal confinement buildings (Compl. ¶16). The complaint alleges it includes a variable rate heater, a temperature sensor, and a controller that manages heat output (Compl. ¶¶ 17-18).
- The complaint alleges the VariFlame controller functions by accepting a user set point, measuring the current temperature, and determining the difference (Compl. ¶¶ 19-20). It further alleges the controller maintains a "dead-band" where output is unchanged (Compl. ¶21), but when the temperature difference exceeds the dead-band, it "determines an error correction based on both the difference and on one or more past error corrections" to adjust the heat output (Compl. ¶22).
- No probative visual evidence provided in complaint.
IV. Analysis of Infringement Allegations
The complaint alleges that the VariFlame system infringes each element of Claim 1 of the '937 Patent.
'937 Patent Infringement Allegations
| Claim Element (from Independent Claim 1) | Alleged Infringing Functionality | Complaint Citation | Patent Citation |
|---|---|---|---|
| a variable rate heater which, when turned on, has a heat output ranging from a minimum heat output percent to a maximum heat output percent... | The VariFlame includes a variable rate heater with a heat output ranging from a minimum to a maximum percent, where the minimum is smaller than the maximum. | ¶17 | col. 18:55-62 |
| a temperature sensor; and a controller for managing the variable rate heater and the heat output thereof | The VariFlame system includes a temperature sensor and a controller for managing the heater and its output. | ¶18 | col. 18:63-66 |
| the system accepts a heat set point temperature from a user and measures a current temperature using the temperature sensor | The VariFlame system accepts a heat set point temperature from a user and measures the current temperature. | ¶19 | col. 18:67 - col. 19:2 |
| the controller determines a difference between the current temperature and the heat set point temperature | The VariFlame controller determines the difference between the current temperature and the set point. | ¶20 | col. 19:3-5 |
| while the difference is no greater than a dead-band value, the controller leaves the heat output of the variable rate heater unchanged at a current heat output | If the temperature difference is within a "dead-band value," the VariFlame controller leaves the heat output unchanged. | ¶21 | col. 19:6-9 |
| determines an error correction based on both the difference and on one or more past error corrections... | If the difference is greater than the dead-band, the controller determines an error correction based on the current difference and "one or more past error corrections" derived from prior temperature readings. | ¶22 | col. 19:12-15 |
| sets the heat output of the variable rate heater to an adjusted heat output based on the error correction | The system sets the heater's output to an adjusted level based on the calculated error correction. | ¶23 | col. 19:15-17 |
| if the heat output... remains at the minimum heat output percent without being adjusted upwards for a timeout period, the controller turns off... the heater | If the VariFlame unit's output remains at its minimum for a "timeout period," the controller turns the heater off. | ¶25 | col. 19:26-30 |
- Identified Points of Contention:
- Technical Questions: The complaint’s allegations mirror the claim language closely. A primary factual question for discovery and trial will be whether the accused VariFlame controller's software actually implements the specific logic claimed. The key will be what evidence supports the allegation that the VariFlame's algorithm determines an "error correction based on...one or more past error corrections" (Compl. ¶22), which is the integral component of the control logic described in the patent ('937 Patent, col. 8:4-11).
V. Key Claim Terms for Construction
- The Term: "error correction based on both the difference and on one or more past error corrections"
- Context and Importance: This limitation defines the core intelligence of the claimed controller, distinguishing it from simpler thermostats. Its construction is critical because it dictates whether the claim covers only specific types of advanced algorithms (like the one disclosed) or a broader range of predictive or adaptive controls. Practitioners may focus on this term as it appears to be the central technical novelty.
- Intrinsic Evidence for Interpretation:
- Evidence for a Broader Interpretation: The claim language itself does not recite the specific terms "Proportional-Integral" or "PI," nor does it contain any mathematical equations. A party may argue that the plain meaning covers any algorithm that considers both the present state (the "difference") and some form of historical error data, regardless of the precise implementation.
- Evidence for a Narrower Interpretation: A party may argue that the specification defines the term by consistently and exclusively describing it as a "Proportional+Integral ('PI')” control loop ('937 Patent, col. 8:4-5, col. 10:20-25). The patent states that the "integral function provides the ability to 'lock' in to a specific temperature" by accumulating "past errors" ('937 Patent, col. 10:7-8, col. 13:14-15), suggesting this integral function is a required aspect of the claimed "error correction."
VI. Other Allegations
- Indirect Infringement: The prayer for relief includes requests for findings of contributory and induced infringement (Compl., Prayer for Relief A), but the complaint's single count for infringement is pleaded exclusively as direct infringement under 35 U.S.C. § 271(a) (Compl. ¶28). The complaint does not provide specific factual allegations to support the knowledge and intent elements required for indirect infringement claims.
- Willful Infringement: The complaint alleges that "at all material times, GSI had knowledge that one or more of the VariFlame systems infringed Claim 1" and that its infringement was "knowing[], willing[], and deliberate[]" (Compl. ¶31; Prayer for Relief B). The complaint does not, however, state the basis for this alleged pre-suit knowledge, such as a prior notice letter or other communication.
VII. Analyst’s Conclusion: Key Questions for the Case
The resolution of this dispute may depend on the answers to two central questions:
A core issue will be one of claim construction: will the term "error correction based on... one or more past error corrections" be interpreted narrowly to require the specific Proportional-Integral (PI) control logic detailed in the patent's specification, or will it be construed more broadly to cover other types of algorithms that use historical data?
A key evidentiary question will be one of algorithmic function: does the accused VariFlame controller, as a matter of technical fact, operate using a control logic that relies on "one or more past error corrections" to adjust its output, as required by Claim 1, or does it achieve variable-rate heating through a different, non-infringing method?