Luminatronics LLC v. Bourns Inc

I. Executive Summary and Procedural Information

• Parties & Counsel:
  • Plaintiff: Luminatronics LLC (Delaware)
  • Defendant: Bourns, Inc. (California)
  • Plaintiff’s Counsel: Rabicoff Law LLC
• Case Identification: 4:25-cv-00111, E.D. Tex., 02/06/2025
• Venue Allegations: Venue is alleged to be proper based on Defendant maintaining an established place of business within the Eastern District of Texas and having committed alleged acts of infringement in the district.
• Core Dispute: Plaintiff alleges that Defendant infringes a patent related to electronic circuits for driving Light Emitting Diodes (LEDs).
• Technical Context: The technology concerns driver circuits that improve the power factor and efficiency of LED lights powered by an alternating current (AC) source, a key consideration in the design of modern solid-state lighting.
• Key Procedural History: The complaint states that Plaintiff is the assignee of the patent-in-suit. No other procedural events, such as prior litigation or administrative proceedings, are mentioned.

Case Timeline

II. Technology and Patent(s)-in-Suit Analysis

U.S. Patent No. 9,807,836 - "Light emitting diode light structures"

• Issued: October 31, 2017

The Invention Explained

• Problem Addressed: The patent describes a problem inherent in powering LEDs from a standard AC mains supply. Because LEDs only turn on above a certain voltage, they only draw current during the peaks of the AC voltage waveform. This results in a poor power factor (inefficient use of power from the grid) and can cause perceptible flicker in the light output (’836 Patent, col. 2:46-68).
• The Patented Solution: The invention proposes a circuit that dynamically adjusts the number of active LEDs in a series string in response to the changing AC voltage. The circuit uses control logic to sense the level of the rectified voltage. When the voltage is low (in the troughs of the AC cycle), the circuit bypasses, or "shunts," a portion of the LEDs in the string. This allows the remaining LEDs to activate at a lower overall voltage, causing the light to turn on sooner and stay on longer during each AC cycle, thereby improving the power factor and smoothing the light output (’836 Patent, Abstract; col. 7:6-31; Fig. 6).
• Technical Importance: This design aims to achieve high power factor and low flicker in a simpler, more efficient manner than traditional solutions, which often require more complex and costly power conversion electronics (’836 Patent, col. 8:1-11).

Key Claims at a Glance

• The complaint does not specify which claims are asserted, referring generally to "one or more claims" and "Exemplary '836 Patent Claims" identified in a non-provided exhibit (Compl. ¶11). The patent's independent claims are 1 and 8.
• Independent Claim 1 recites an apparatus comprising:
  • a bridge rectifier to produce a rectified output;
  • control circuitry to produce a shunt signal when the rectified output is less than a threshold voltage;
  • a series-connected LED string with a first group and a second group of LEDs; and
  • a switch, controlled by the shunt signal, to "deactivate" the second group of LEDs.
• Independent Claim 8 recites a similar apparatus with three groups of LEDs and two corresponding switches, each controlled by a separate shunt signal triggered at different voltage thresholds.
• The complaint’s general allegation of infringing "one or more claims" suggests Plaintiff reserves the right to assert dependent claims in addition to the independent claims.

III. The Accused Instrumentality

Product Identification

The complaint does not identify any specific accused products by name. It refers to "Exemplary Defendant Products" that are purportedly identified in charts within "Exhibit 2" (Compl. ¶11). This exhibit was not provided with the complaint.

Functionality and Market Context

The complaint does not provide any technical description of how the accused products operate. It makes general allegations that Defendant makes, uses, sells, and internally tests products that "practice the technology claimed by the '836 Patent" (Compl. ¶¶11, 12, 16). The complaint does not provide sufficient detail for analysis of the accused instrumentality's functionality or market position.

IV. Analysis of Infringement Allegations

The complaint alleges infringement but incorporates the specific comparisons into an external "Exhibit 2" which was not provided (Compl. ¶¶16, 17). The complaint itself contains no claim charts or detailed infringement theories. No probative visual evidence provided in complaint. A substantive analysis of the infringement allegations is therefore not possible based on the provided documents. The core of the infringement allegation is the summary statement that "the Exemplary Defendant Products practice the technology claimed by the '836 Patent" (Compl. ¶16).

• Identified Points of Contention: Based on the claim language, several points of contention may arise during litigation.
  • Scope Questions: A central question may be the meaning of "deactivate" in Claim 1. The dispute could center on whether this term requires the LEDs to be completely shut off or if it can be met by the shunting/bypassing action described in the patent's specification (’836 Patent, col. 7:28-31), where current is routed around a group of LEDs.
  • Technical Questions: The infringement case will depend on evidence that the accused products contain "control circuitry" that functions as claimed—specifically, by generating a "shunt signal when the rectified output is less than a threshold voltage." A key question will be whether the accused products' circuitry performs this specific voltage-dependent logical operation or achieves a similar outcome through a technically distinct method.

V. Key Claim Terms for Construction

• The Term: "deactivate" (from Claim 1)

  • Context and Importance: This term defines the action performed by the switch on the second group of LEDs. Its construction is critical because it determines what functionality an accused product must have to infringe. Practitioners may focus on this term to argue for a narrow construction tied to the patent's specific embodiments or a broader one covering any method of rendering the LEDs non-operational.
  • Intrinsic Evidence for Interpretation:
    • Evidence for a Broader Interpretation: The term itself, given its plain and ordinary meaning, could be interpreted broadly to mean rendering inoperative, turning off, or disabling by any means.
    • Evidence for a Narrower Interpretation: The specification consistently describes the inventive action as shunting current across a group of LEDs using a switch (e.g., a transistor) to create a bypass path (’836 Patent, col. 8:56-63). A party could argue that "deactivate" should be limited to this specific shunting mechanism.

• The Term: "control circuitry ... configured to produce a shunt signal when the rectified output is less than a threshold voltage" (from Claim 1)

  • Context and Importance: This limitation describes the "trigger" for the claimed invention. Proving infringement requires showing that an accused device's circuitry is designed to perform this precise conditional logic.
  • Intrinsic Evidence for Interpretation:
    • Evidence for a Broader Interpretation: A party might argue that any circuit that has the net effect of bypassing LEDs when the input voltage is low meets this limitation, focusing on the functional result rather than the specific implementation.
    • Evidence for a Narrower Interpretation: The specification discloses specific embodiments for the control circuitry, such as a "ratio metric series resistor string and an inverter" (’836 Patent, col. 7:13-16; Fig. 7A). A defendant could argue that the term "control circuitry" should be construed as limited to these disclosed structures or their equivalents.

VI. Other Allegations

• Indirect Infringement: The complaint alleges induced infringement, stating that Defendant sells the accused products to customers and provides "product literature and website materials" that allegedly direct end users to use the products in an infringing manner (Compl. ¶¶14, 15).
• Willful Infringement: The complaint alleges that its service constitutes "actual knowledge" of infringement (Compl. ¶13). It further alleges that Defendant's continued infringing activities after receiving this notice are willful, which could form the basis for a claim of enhanced damages (Compl. ¶14).

VII. Analyst’s Conclusion: Key Questions for the Case

• A primary issue will be evidentiary and factual: As the complaint lacks specific details about the accused products, the case will turn on the evidence Plaintiff can produce to demonstrate that Defendant's products contain control circuitry that performs the precise, voltage-dependent switching function recited in the '836 Patent’s claims.
• The central legal issue will be one of claim construction: The interpretation of key terms, particularly "deactivate" and "control circuitry", will be dispositive. Whether these terms are given a broad functional meaning or are narrowed to the specific circuit topologies disclosed in the patent will likely determine the outcome of the infringement analysis.