DCT

5:25-cv-00078

LG Display Co Ltd v. Tianma Microelectronics Co Ltd

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I. Executive Summary and Procedural Information

  • Parties & Counsel:
  • Case Identification: 5:25-cv-00078, E.D. Tex., 06/13/2025
  • Venue Allegations: Plaintiff alleges that venue is proper because all Defendants are foreign corporations and not residents of the United States, allowing them to be sued in any judicial district.
  • Core Dispute: Plaintiff alleges that Defendant’s LCD and OLED display panels, incorporated into automotive and mobile products sold in the U.S., infringe seven U.S. patents related to display device structure, electrostatic discharge protection, and touch-sensing technology.
  • Technical Context: The dispute centers on foundational technologies for modern OLED and LCD panels, which are critical components in a vast market of consumer and automotive electronics.
  • Key Procedural History: The complaint details a nearly decade-long history of licensing negotiations between LG Display and Tianma (and its corporate predecessors), beginning after a 2011 joint venture between Tianma’s parent company and NEC, which had a prior license with LG Display. Plaintiff alleges it provided Defendant with multiple notices of infringement, including claim charts for several of the asserted patents, starting as early as 2015 and specifically identifying four of the now-asserted patents in October 2021.

Case Timeline

Date Event
2008-12-24 ’166 Patent Priority Date
2010-06-22 ’801 Patent Priority Date
2011-02-25 NEC and AVIC (Tianma's parent) announce capital alliance
2012-05-05 ’803 Patent Priority Date
2013-04-09 ’166 Patent Issue Date
2013-04-10 ’493 Patent Priority Date
2013-07-30 ’388 Patent Priority Date
2014-05-27 ’801 Patent Issue Date
2015-01-30 ’924 Patent Priority Date
2015-07-01 LGD and Tianma hold first licensing meeting (approx. July 2015)
2015-10-15 LGD sends letter with 11 claim charts to Tianma
2016-06-30 ’394 Patent Priority Date
2019-01-08 ’803 Patent Issue Date
2019-10-15 ’924 Patent Issue Date
2019-12-03 ’493 Patent Issue Date
2020-12-15 ’388 Patent Issue Date
2021-10-28 LGD presents claim charts for ’803 and ’924 Patents to Tianma
2021-10-29 LGD sends notice including ’493 and ’388 Patents to Tianma
2022-02-15 ’394 Patent Issue Date
2025-06-13 Complaint Filing Date

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

U.S. Patent No. 8,416,166 - "Liquid Crystal Display Device" (Issued Apr. 9, 2013)

The Invention Explained

  • Problem Addressed: The patent’s background section describes how leakage current from electrostatic discharge (ESD) circuits can cause display defects, such as horizontal lines, and increase power consumption in LCD devices (’166 Patent, col. 1:11-37). Conventional designs connected ESD protection circuits directly between a common voltage line and the data/gate lines, creating a path for such leakage.
  • The Patented Solution: The invention introduces a "floating line" that is physically positioned between the common voltage line and the data/gate lines around the periphery of the display area (’166 Patent, Fig. 2). This floating line is electrically isolated from the common voltage line during normal operation. ESD protection circuits are arranged to connect the common line to the floating line, and the floating line to the data and gate lines, creating a multi-stage discharge path that isolates the display circuitry from leakage current originating at the common line. (’166 Patent, Abstract; col. 2:20-31).
  • Technical Importance: This architecture aims to enhance the electrostatic robustness and visual quality of LCD panels by mitigating a known cause of defects and power drain, without adding significant manufacturing complexity (’166 Patent, col. 1:11-37).

Key Claims at a Glance

  • The complaint asserts independent claim 1 (Compl. ¶90).
  • The essential elements of claim 1 include:
    • A display area and a non-display area with crossing gate and data lines.
    • A "floating line" disposed along the periphery of the display area to maintain a "floating state".
    • A "common line" disposed along the periphery of the floating line to apply a common voltage.
    • Three sets of electrostatic dischargers: first (common line to floating line), second (floating line to gate lines), and third (floating line to data lines).
    • The floating line is "electrically disconnected" from the common line.
    • "No voltage is applied" to the floating line, while a common voltage is applied to the common line.
  • The complaint reserves the right to assert additional claims (Compl. ¶79).

U.S. Patent No. 8,736,801 - "Display Panel and Display Device Comprising the Same" (Issued May 27, 2014)

The Invention Explained

  • Problem Addressed: The patent specification focuses on the physical layout of grounding structures in a display panel, suggesting that the problem being addressed is the effective management of grounding and electrostatic discharge in panel designs where data connections (pad portions) are concentrated on one side (’801 Patent, col. 1:44-51).
  • The Patented Solution: The invention specifies a ground line architecture on the display's lower substrate. A key feature is a "first ground line" that connects the first data pad portion to the last data pad portion along one side of the display. This ground line then "extends along all of the side regions of the display area except for the first side region" without being broken up by any other pads, creating a continuous, U-shaped grounding path around three sides of the active display area. (’801 Patent, Abstract; col. 4:1-20).
  • Technical Importance: This continuous ground line structure provides a robust and uninterrupted path for dissipating static electricity, which can reduce signal interference and prevent ESD-related damage, thereby improving the overall reliability of the display panel (’801 Patent, Abstract).

Key Claims at a Glance

  • The complaint asserts independent claim 1 (Compl. ¶121).
  • The essential elements of claim 1 include:
    • A lower substrate with a display area and a non-display area.
    • A plurality of "data pad portions" formed at the non-display area adjacent to a "first side region".
    • An upper substrate bonded to the lower substrate, except for the area with the data pad portions.
    • At least one ground line that includes a "first ground line" connecting a first data pad portion to a last data pad portion.
    • The first ground line, "without separation by any pad portions", "extends along all of the side regions of the display area except for the first side region".
  • The complaint reserves the right to assert additional claims (Compl. ¶79).

Multi-Patent Capsules

  • U.S. Patent No. 10,175,803, "Touch Sensing Device and Method for Driving the Same" (Issued Jan. 8, 2019)

    • Technology Synopsis: The patent addresses electrical noise that interferes with touch sensing in integrated touch-and-display panels (’803 Patent, col. 2:18-26). The proposed solution is a driving method that divides the touch operation into distinct periods and performs the sensitive capacitance measurement only during an "optimum sensing time" when electrical interference from the display's gate lines is minimal, thereby improving touch detection accuracy (’803 Patent, Abstract).
    • Asserted Claims: Independent claim 1 is asserted (Compl. ¶147).
    • Accused Features: The complaint accuses the touch sensing functionality of the LCD display panel incorporated into the Moto G Stylus smartphone (Compl. ¶¶81, 149-151).

  • U.S. Patent No. 10,444,924, "Touch Display Apparatus" (Issued Oct. 15, 2019)

    • Technology Synopsis: This patent seeks to improve image quality in in-cell touch displays by reducing the electrical load of touch electrodes and minimizing load variations between them (’924 Patent, col. 2:19-25). The invention describes a touch electrode structure comprising bridges that connect different portions of the electrode and conductive lines that are used to drive the electrode with both a common voltage for image display and a touch signal for sensing (’924 Patent, Abstract; Claim 1).
    • Asserted Claims: Independent claim 1 is asserted (Compl. ¶192).
    • Accused Features: The complaint accuses the touch display panel structure within the Moto G Stylus smartphone (Compl. ¶¶81, 194-196).

  • U.S. Patent No. 10,499,493, "Flexible Display Device and Method of Manufacturing the Same" (Issued Dec. 3, 2019)

    • Technology Synopsis: The invention relates to the mechanical assembly of a flexible display, focusing on a design where the portion of the substrate with the driver IC is bent underneath the main display area to reduce bezel size (’493 Patent, Abstract). The patent describes a specific structure including a flexible substrate with a display area, a bent part, and a pad part, where the substrate in the bent part has a "second width smaller than the first width" of the display area, in combination with a supporting member (’493 Patent, Claim 9).
    • Asserted Claims: Independent claim 9 is asserted (Compl. ¶225).
    • Accused Features: The complaint accuses the flexible OLED display panel, identified as part number TA067FVWK15-01-MRF3-00, incorporated into the Motorola edge+ smartphone (Compl. ¶¶83, 227-229).

  • U.S. Patent No. 10,869,388, "Display Device" (Issued Dec. 15, 2020)

    • Technology Synopsis: This patent also describes a mechanical structure for a flexible display with a bent-under configuration (’388 Patent, col. 1:19-25). The solution involves a multi-part "back film" adhered to the bottom of the flexible substrate, with a distinct gap in the film that corresponds to the device's bending part. It also specifies a supporting member that is not bent and extends beyond an outer edge of the display part to provide rigidity. (’388 Patent, Abstract).
    • Asserted Claims: Independent claim 12 is asserted (Compl. ¶250).
    • Accused Features: The complaint accuses the OLED display panel, identified as part number TA067FVWK15-15-MRF1-00, incorporated into the Xiaomi 13T smartphone (Compl. ¶¶84, 252-254).

  • U.S. Patent No. 11,251,394, "Organic Light Emitting Display and Method of Fabricating the Same" (Issued Feb. 15, 2022)

    • Technology Synopsis: The invention describes an on-cell touch structure for OLED displays, where the touch sensor components are integrated directly on top of the thin-film encapsulation layer that protects the organic light-emitting elements (’394 Patent, col. 2:4-14). This eliminates the need for a separate touch panel, making the display thinner. The claims detail the specific layered arrangement of touch electrodes, bridges, conductive lines, and insulating films relative to the underlying pixel bank layer. (’394 Patent, Abstract; Claim 1).
    • Asserted Claims: Independent claim 1 is asserted (Compl. ¶273).
    • Accused Features: The complaint accuses the on-cell touch OLED display panel incorporated into the Motorola edge+ smartphone (Compl. ¶¶83, 275-277).

III. The Accused Instrumentality

Product Identification

  • The complaint collectively identifies the accused instrumentalities as "Accused Products," which are categorized as "Accused Auto LCD Tianma Products," "Accused Mobile LCD Tianma Products," and "Accused Mobile OLED Tianma Products" (Compl. ¶77). Specific examples cited include:
    • An 11" LCD display panel used in the Chevrolet Equinox EV driver information cluster (Compl. ¶79, ¶92).
    • Tianma Panel ID 678FYMM01, an LCD panel used in the Moto G Stylus smartphone (Compl. ¶81).
    • OLED display panels (TA067FVWK15-01-MRF3-00 and TA067FVWK15-15-MRF1-00) used in the Motorola edge+ and Xiaomi 13T smartphones, respectively (Compl. ¶¶83-84).

Functionality and Market Context

  • The accused products are display panels that form the visual interface for automotive infotainment systems and consumer mobile devices (Compl. ¶¶17, 79, 81, 83-84). The complaint alleges that Defendant Tianma is a major global manufacturer of these panels and a direct competitor to Plaintiff LG Display, supplying components to major brands such as General Motors, Motorola Mobility, and Xiaomi (Compl. ¶¶20, 23-24). The complaint includes an image showing the disassembly of a Moto G Stylus, identifying the display module with "Tianma's Panel ID" on the flex cable (Compl. p. 27).

IV. Analysis of Infringement Allegations

’166 Patent Infringement Allegations

Claim Element (from Independent Claim 1) Alleged Infringing Functionality Complaint Citation Patent Citation
a floating line disposed along the periphery of the display area to maintain a floating state The accused 11" LCD panel allegedly includes a conductive line around the display periphery that is maintained in a floating state. ¶95-96 col. 2:24-25
a common line disposed along the periphery of the floating line to apply a common voltage The accused panel allegedly has a common line located along the periphery of the floating line that is supplied with a common voltage. ¶97-98 col. 2:25-26
a plurality of first electrostatic dischargers connected between the common line and the floating line The accused panel allegedly includes ESD protection circuits connecting the common line and the floating line. ¶99-100 col. 2:26-28
a plurality of second electrostatic dischargers connected between the floating line and the gate lines The accused panel allegedly includes ESD protection circuits connecting the floating line to the gate lines that control pixel rows. ¶101-102 col. 2:28-29
a plurality of third electrostatic dischargers connected between the floating line and the data lines The accused panel allegedly includes ESD protection circuits connecting the floating line to the data lines that supply pixel information. ¶103-104 col. 2:29-31
the floating line is electrically disconnected from the common line The accused panel's floating line is allegedly electrically disconnected from its common line, except during an ESD event. ¶105-106 col. 2:31-32
no voltage is applied to the floating line and a common voltage is applied to the common line Plaintiff alleges that in the accused panel, no operating voltage is applied to the floating line, while a common voltage is applied to the common line. ¶107-108 col. 2:33-35
  • Identified Points of Contention:
    • Scope Questions: A central question may be the construction of "floating state" and "no voltage is applied." A defendant could argue that incidental, parasitic, or induced voltages on the accused line mean that "no voltage" is applied is not met, or that capacitive coupling prevents a true "floating state."
    • Technical Questions: The complaint alleges the floating line is disconnected "except when shorted by the static electricity," which describes the intended function of the ESD discharger (Compl. ¶106). An evidentiary question will be whether Plaintiff can prove the precise connectivity and electrical behavior of these microscopic circuits in the accused products to satisfy each of the "first," "second," and "third" discharger limitations. The complaint provides an annotated micrograph showing the alleged physical separation between the common line and floating line (Compl. p. 39).

’801 Patent Infringement Allegations

Claim Element (from Independent Claim 1) Alleged Infringing Functionality Complaint Citation Patent Citation
a plurality of data pad portions formed at the non-display area adjacent to a first side region of the display area The accused 11" LCD panel allegedly has its data connection pads grouped together along one side of the display. ¶126-127 col. 4:3-5
an upper substrate bonded to the lower substrate, except for the non-display area adjacent to the first side region... The accused panel's top substrate is allegedly bonded to the bottom substrate, leaving the data pad area exposed for connection. The complaint provides a cross-section diagram to illustrate this structure (Compl. p. 46). ¶128-129 col. 4:6-9
at least one ground line...including a first ground line connected between a first data pad portion and a last data pad portion... The accused panel is alleged to have a ground line that connects the first and last data pads in the group of data pad portions. ¶130-132 col. 4:13-17
the first ground line, without separation by any pad portions, extends along all of the side regions of the display area except for the first side region The accused panel's ground line allegedly continues from the pad area to trace a U-shaped path around the other three sides of the display area as a continuous, unbroken conductor. ¶133-134 col. 4:17-20
  • Identified Points of Contention:
    • Scope Questions: The interpretation of "extends along all of the side regions" may be a point of dispute. A defendant might argue that this requires a perfectly contiguous line following the exact perimeter, and that any breaks, significant deviations, or non-conductive sections in the accused product's ground line would mean it does not extend along "all" three regions.
    • Technical Questions: The complaint's allegations rely on visual analysis of the accused panel's circuitry, as shown in an annotated photograph of the panel's periphery (Compl. p. 49). The key technical question will be whether the conductive trace identified as the "first ground line" is, in fact, a single, continuous line "without separation" and whether it functions as the ground line as claimed.

V. Key Claim Terms for Construction

For the ’166 Patent

  • The Term: "floating line" / "maintain a floating state"
  • Context and Importance: This term is the central inventive concept of the ’166 Patent. The infringement analysis depends entirely on whether the accused device contains a line that is electrically isolated from the common voltage line during normal operation. Practitioners may focus on this term because its definition will determine if the accused structure, which may have some level of capacitive coupling or incidental voltage, falls within the claim scope.
  • Intrinsic Evidence for Interpretation:
    • Evidence for a Broader Interpretation: The patent abstract describes the line simply as being "disposed between" other lines. The claim language itself adds further limitations (e.g., "electrically disconnected"), which may suggest that "floating state" is a general term defined by those more specific limitations, rather than implying absolute electrical isolation.
    • Evidence for a Narrower Interpretation: The claim explicitly requires that "no voltage is applied to the floating line" (’166 Patent, col. 6:64-65). A defendant may argue this requires a complete absence of any applied or induced potential, a strict condition that might be difficult to prove or disprove in a complex circuit. The embodiment in Figure 2 shows a distinct physical separation, which could be argued to define the required disconnected state.

For the ’801 Patent

  • The Term: "extends along all of the side regions of the display area except for the first side region"
  • Context and Importance: This phrase defines the specific geometry and continuity of the claimed ground line. The infringement case hinges on whether the accused ground line follows this precise U-shaped path around three sides of the display. Practitioners may focus on this term because the words "all" and "extends along" create a potential point of contention regarding the required degree of continuity and proximity to the display area edge.
  • Intrinsic Evidence for Interpretation:
    • Evidence for a Broader Interpretation: One might argue that "extends along" means generally following the periphery of the three sides, allowing for minor engineering-related deviations or gaps that do not functionally interrupt the grounding purpose of the line.
    • Evidence for a Narrower Interpretation: The phrase "without separation by any pad portions" (’801 Patent, col. 6:49-50) paired with "extends along all" could support a strict interpretation requiring a physically and electrically continuous, unbroken conductor that traces the perimeter of the three specified sides. The patent's Figure 3 depicts such a clean, uninterrupted line, which a defendant might offer as defining the claimed structure.

VI. Other Allegations

  • Indirect Infringement: The complaint alleges that Tianma induces infringement by supplying the accused display panels to its customers (e.g., General Motors, Motorola) with the knowledge and intent that they will be incorporated into infringing end-products sold in the U.S. (Compl. ¶¶110, 136). The complaint also alleges contributory infringement, asserting the panels are a material part of the patented inventions and are not staple articles of commerce suitable for substantial non-infringing use (Compl. ¶¶111, 137).
  • Willful Infringement: The complaint makes detailed allegations of willful infringement based on a long history of communication and licensing negotiations. It is alleged that Tianma had actual knowledge of LG Display's patent portfolio and specific notice of infringement of at least four of the asserted patents through claim charts provided in October 2021, nearly four years before the complaint was filed (Compl. ¶¶66-67, 115, 141). The continuation of allegedly infringing activities despite this long-standing notice is presented as evidence of willful, deliberate infringement.

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

  • A primary issue will be one of willfulness and intent: given the extensive pre-suit history of notices and licensing negotiations detailed in the complaint, can Plaintiff establish that Defendant’s alleged infringement was objectively reckless and deliberately indifferent to a high likelihood of infringing valid patents, potentially justifying enhanced damages?
  • A second core issue will be one of definitional scope and claim construction: can the term "floating line" in the ’166 Patent be construed to read on a circuit component that may be subject to incidental voltages or capacitive coupling, and can the geometric limitation "extends along all...side regions" in the ’801 Patent be construed to read on a physical trace that may have manufacturing-related imperfections or deviations from a perfect perimeter?
  • A key evidentiary question will be one of technical proof: across a portfolio of seven patents covering distinct technologies from ESD protection to flexible display mechanics, can Plaintiff provide sufficient reverse-engineering evidence to demonstrate that Tianma's mass-produced products meet every specific structural and functional limitation recited in the asserted claims?