DCT

2:23-cv-00165

Longitude Licensing Ltd v. Sharp Corp

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I. Executive Summary and Procedural Information

  • Parties & Counsel:
  • Case Identification: 2:23-cv-00165, E.D. Tex., 04/11/2023
  • Venue Allegations: Venue is alleged as proper under 28 U.S.C. § 1391(c)(3), which permits suing a foreign defendant that does not reside in the United States in any judicial district.
  • Core Dispute: Plaintiff alleges that Defendant’s liquid crystal display (LCD) devices, panels, and modules infringe seven patents related to foundational LCD technologies, including pixel layouts, electrode structures, and protective circuits.
  • Technical Context: The technology at issue involves fundamental aspects of LCD panel design and manufacturing, a critical component technology for a vast range of electronic products, including televisions, automotive displays, and mobile devices.
  • Key Procedural History: The complaint details extensive pre-suit licensing negotiations between the parties, allegedly beginning around March 2019 and continuing until November 2022. Plaintiff asserts that during these negotiations, it provided Defendant with actual notice of the patents-in-suit and claim charts identifying allegedly infringing products, forming the basis for its willful infringement allegations.

Case Timeline

Date Event
2002-05-02 ’500 Patent Priority Date
2003-08-29 ’353 Patent Priority Date
2004-07-05 ’462 Patent Priority Date
2004-10-19 ’500 Patent Issue Date
2004-12-27 ’606 Patent Priority Date
2006-10-13 ’948 Patent Priority Date
2006-10-25 ’171 Patent Priority Date
2007-03-27 ’353 Patent Issue Date
2009-03-23 ’512 Patent Priority Date
2010-04-27 ’948 Patent Issue Date
2011-06-14 ’171 Patent Issue Date
2012-11-27 ’512 Patent Issue Date
2017-01-31 ’606 Patent Issue Date
2018-01-01 Approx. Launch of LG 70UK65 TV & Vizio E70-F3 TV
2019-01-01 Approx. Launch of 2019 Ford F-150
2019-03-01 Alleged Start of Licensing Negotiations
2019-01-15 ’462 Patent Issue Date
2020-01-01 Approx. Launch of 2020 Toyota Corolla
2020-05-01 Approx. Launch of Microsoft Surface Go 2
2021-01-01 Approx. Launch of 2021 Mazda CX-9 & LG 70UP80 TV
2023-04-11 Complaint Filing Date

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

U.S. Patent No. 6,806,500 - “Electro-Optical Device and Electronic Apparatus,” issued October 19, 2004

The Invention Explained

  • Problem Addressed: The patent background describes how moisture can enter thin-film transistors (TFTs) in an electro-optical device, generating positive charges that degrade image quality and shorten the device's operational lifetime (U.S. Patent 6,806,500, col. 1:40-54).
  • The Patented Solution: The invention proposes disposing a dense nitride film over at least the surfaces of the data lines within the display's pixel array. This film acts as a barrier to prevent moisture from reaching the TFTs, thereby prolonging the device's stability and operational life (U.S. Patent 6,806,500, Abstract; col. 2:23-30). The complaint alleges this provides for brighter, higher-quality images (Compl. ¶13).
  • Technical Importance: This approach provided a method for enhancing the durability and performance of LCDs, which were increasingly critical components in the expanding consumer and industrial electronics markets of the early 2000s (Compl. ¶13).

Key Claims at a Glance

  • The complaint asserts independent claim 4 and dependent claims 5 and 10 (Compl. ¶55).
  • Independent Claim 4 requires:
    • An electro-optical device comprising a first substrate, scanning lines, data lines, thin film transistors, and pixel electrodes.
    • A nitride film disposed at least on surfaces of the data lines.
    • The nitride film is also formed in the periphery of an image display region.
    • The nitride film extends only on the data lines, in addition to being in the periphery of the image display region.

U.S. Patent No. 7,196,353 - “Electro-Optical Device and Electronic Apparatus,” issued March 27, 2007

The Invention Explained

  • Problem Addressed: The patent addresses image quality degradation, particularly near the edges of a display, caused by stray diagonal or reflected light entering a "dummy area" that surrounds the active image display area (U.S. Patent 7,196,353, col. 1:47-67).
  • The Patented Solution: The invention introduces a "dummy-pixel light-shielding film" that covers the openings of "dummy pixels" located in a frame-shaped region around the main display area. By placing this shielding film on a layer below the device's wiring and electronic elements, it blocks stray light components, thereby sharpening the edges of the resulting image (U.S. Patent 7,196,353, Abstract; col. 2:20-36).
  • Technical Importance: This invention aimed to improve perceived image quality by correcting specific visual artifacts at the screen's border, enhancing sharpness and contrast where the image meets the bezel (Compl. ¶14).

Key Claims at a Glance

  • The complaint asserts independent claim 1 and claims 2-10, 13, and 15 (Compl. ¶80).
  • Independent Claim 1 requires:
    • An electrooptical device with a plurality of pixel electrodes, and wires/electronic elements to drive them.
    • An image display area containing a first set of pixel electrodes.
    • A frame-shaped dummy area surrounding the image display area, containing a second set of pixel electrodes.
    • A dummy-pixel light-shielding film covering at least part of the opening regions of the dummy pixel electrodes.
    • The dummy-pixel light-shielding film is formed on a lower layer side of the wires and electric elements.

U.S. Patent No. 7,705,948

  • Patent Identification: U.S. Patent No. 7,705,948, “Liquid Crystal Display Device,” issued April 27, 2010 (Compl. ¶15).
  • Technology Synopsis: The patent is directed to specific geometries for slits within liquid crystal pixel structures. The claimed geometries are intended to reduce an optical artifact known as disclination at the ends of the slits, which in turn improves light transmission and overall image quality (Compl. ¶15).
  • Asserted Claims: At least claims 1, 5, and 6 are asserted (Compl. ¶103).
  • Accused Features: The complaint accuses the geometry of slits in the accused LCD panels, specifically alleging the presence of first and second curved portions at the slit edges, where the second curved portion is smaller and includes a projecting portion at its distal end (Compl. ¶¶105, 119).

U.S. Patent No. 7,961,171

  • Patent Identification: U.S. Patent No. 7,961,171, “Electrooptic Device and Electronic Apparatus,” issued June 14, 2011 (Compl. ¶16).
  • Technology Synopsis: The patent describes a novel pixel circuit configuration involving multiple transistors and multiple scan lines associated with each pixel. This architecture is intended to provide benefits such as more flexible operation of the display device (Compl. ¶16).
  • Asserted Claims: At least claims 1, 17, and 19 are asserted (Compl. ¶132).
  • Accused Features: The complaint accuses pixels arranged in a matrix that each allegedly include first and second transistors connected to first and second sets of scan lines and to signal lines in the specific configuration recited in the claims (Compl. ¶134).

U.S. Patent No. 8,319,512

  • Patent Identification: U.S. Patent No. 8,319,512, “Flexible Substrate Including Inspection Electrode for Outputting Signal Processed in Integrated Circuit, Electro-Optical Device, and Electronic Device,” issued November 27, 2012 (Compl. ¶17).
  • Technology Synopsis: The patent relates to inspection terminals (electrodes) mounted on the flexible substrate that connects a display substrate to external electronics. These terminals allow signals processed by a driving circuit chip on the flexible substrate to be tested during manufacturing, thereby improving production yield (Compl. ¶17).
  • Asserted Claims: At least claims 10-12 are asserted (Compl. ¶167).
  • Accused Features: The accused feature is a flexible substrate that includes an inspection electrode electrically connected to an integrated circuit, where the electrode is capable of outputting a signal processed by that circuit for inspection purposes (Compl. ¶¶169, 175-176).

U.S. Patent No. 9,557,606

  • Patent Identification: U.S. Patent No. 9,557,606, “Liquid Crystal Display Device Having Rectangular Close-shape Seal Members,” issued January 31, 2017 (Compl. ¶18).
  • Technology Synopsis: The patent describes an LCD panel manufactured using a "one-drop" fill process, which involves a continuous seal between substrates. The invention arranges conductive portions away from electrical elements crossing the seal, a configuration purported to improve manufacturing speed and reliability over prior methods (Compl. ¶18).
  • Asserted Claims: At least claims 13 and 20 are asserted (Compl. ¶190).
  • Accused Features: The complaint accuses LCD panels of having a continuous, closed-ring seal member between first and second substrates, where the first substrate has a protruding region onto which wiring lines extend across the seal member (Compl. ¶192).

U.S. Patent No. 10,181,462

  • Patent Identification: U.S. Patent No. 10,181,462, “Semiconductor Device, Display Device, and Electronic Apparatus,” issued January 15, 2019 (Compl. ¶19).
  • Technology Synopsis: This patent relates to protecting driving circuitry built into a display substrate from electrostatic shock damage. The invention places two sets of protective circuits on both sides of the driving circuit to shield it from electrostatic discharges that can enter via signal and power lines (Compl. ¶19).
  • Asserted Claims: At least claims 1-3, 5, and 7 are asserted (Compl. ¶220).
  • Accused Features: The complaint accuses LCD modules that include a display substrate with a driving circuit positioned between a first protective circuit arranged at a first corner and a second protective circuit arranged at a second corner of the substrate (Compl. ¶222).

III. The Accused Instrumentality

Product Identification

  • The "Accused Instrumentalities" are broadly defined as Sharp's LCD devices, panels, and modules. This includes both "Accused Sharp Products" (Sharp-branded TVs and displays) and "Accused Sharp LCD Modules" (panels and modules sold to third parties for inclusion in products like TVs, monitors, computers, smartphones, and vehicle infotainment displays) (Compl. ¶¶30-31).

Functionality and Market Context

  • The accused products are components and end-products that incorporate foundational LCD technologies for displaying images (Compl. ¶2). The complaint alleges that Sharp sells these products in the U.S. through its "8K Ecosystem" and "Display Device" business segments (Compl. ¶24). An annotated photo identifies the Sharp model number LS103K5LX01 on a flexible circuit board from a Mazda dashboard display (Compl. p. 19). The complaint alleges significant U.S. sales and revenue from these segments, positioning Sharp as a major supplier to the North American market (Compl. ¶¶26-27).

IV. Analysis of Infringement Allegations

U.S. Patent No. 6,806,500 Infringement Allegations

Claim Element (from Independent Claim 4) Alleged Infringing Functionality Complaint Citation Patent Citation
an electro-optical device comprising: a first substrate; scanning lines; data lines; The Sharp LS103K5LX01 LCD panel is an electro-optical device containing a first substrate with scanning and data lines. ¶59-62 col. 2:13-17
thin film transistors provided above the first substrate corresponding to intersections of the scanning lines and the data lines; The accused panel includes thin film transistors (TFTs) located above the first substrate at the intersections of the scanning and data lines. ¶63-64 col. 2:13-17
pixel electrodes provided corresponding to the thin film transistors; The accused panel has pixel electrodes corresponding to the TFTs. An annotated micrograph shows the location of the TFTs and pixel electrodes relative to the scanning and data lines (Compl. p. 25). ¶65 col. 2:13-17
and a nitride film disposed at least on surfaces of the data lines, the nitride film being formed in the periphery of an image display region that is defined by the region including the pixel electrodes, the scanning lines, and the data lines, The accused panel allegedly includes a nitride film (specifically, TiN) on the surfaces of its data lines and in the periphery of the image display region. ¶66-67 col. 3:10-15
wherein the nitride film extends only on the data lines, in addition to in the periphery of the image display region. The nitride film allegedly extends only on the data lines within the image display region, in addition to its presence in the periphery. An annotated micrograph identifies the pixel array, defined as the "image display region," and the surrounding "periphery" where the nitride film is allegedly formed (Compl. p. 28). ¶68 col. 3:19-23

Identified Points of Contention

  • Scope Questions: A central question may be the construction of "nitride film." The complaint alleges the presence of a Titanium Nitride (TiN) film (Compl. ¶66), whereas the patent specification's examples focus on silicon nitride (U.S. Patent 6,806,500, col. 2:37-39). The dispute may turn on whether the claim term is broad enough to encompass nitrides other than silicon-based compounds. Another question may be the scope of "periphery of an image display region," as infringement depends on the film's specific location.
  • Technical Questions: What evidence demonstrates that the nitride film "extends only on the data lines" within the active display region, as required by the final limitation of claim 4? The complaint's visual evidence shows the film on the data lines but does not conclusively prove its absence elsewhere within the pixel area.

U.S. Patent No. 7,196,353 Infringement Allegations

Claim Element (from Independent Claim 1) Alleged Infringing Functionality Complaint Citation Patent Citation
an electrooptical device comprising: a plurality of pixel electrodes provided above a substrate; at least one of wires and electronic elements that are used to drive the plurality of pixel electrodes; The Sharp LQ080Y5DZ04J LCD panel is an electro-optical device that contains pixel electrodes above a substrate, along with wires (scan and data lines) and electronic elements (TFTs) to drive them. ¶84-86 col. 2:22-25
an image display area where a first set of pixel electrodes among the plurality of pixel electrodes is located; The accused panel has a central image display area containing a first set of pixel electrodes. ¶87 col. 2:25-27
a dummy area where a second set of pixel electrodes among the plurality of pixel electrodes is located, the dummy area having a frame-like shape and surrounding the image display area; The panel allegedly has a frame-shaped "dummy area" surrounding the image display area, which contains a second set of "dummy pixel electrodes." An annotated micrograph shows the central 'Image Display Area' surrounded by a 'Dummy Area' containing 'Dummy Pixel Electrodes,' illustrating this claimed spatial relationship (Compl. p. 40). ¶88 col. 2:27-30
and a dummy-pixel light-shielding film that covers at least part of opening regions of the pixel electrodes that function as dummy pixel electrodes being provided on the substrate, The accused panel allegedly includes a dummy-pixel light-shielding film that covers openings of the dummy pixel electrodes on the substrate. ¶89 col. 2:30-34
the dummy-pixel light-shielding film being formed on a lower layer side of the at least one of wires and electric elements. The light-shielding film is allegedly formed in a lower metal deposition layer ("Metal 1") than the wires and electronic elements, which are in a higher layer ("Metal 2"). ¶90-91 col. 2:34-36

Identified Points of Contention

  • Technical Questions: The complaint's allegation for the final claim element relies on an inference that the layered structure in the active pixel area is the same as in the dummy area (Compl. ¶91). A defendant may challenge this assertion, raising the evidentiary question of whether the light-shielding film is in fact on a "lower layer side" of the relevant wires and elements within the dummy area itself.
  • Scope Questions: Does the structure identified as a "light-shielding film" in the accused product perform the function of shielding light in the manner contemplated by the patent? The interpretation of "covers at least part of opening regions" will also be critical to determining if the alleged structure meets the claim limitation.

V. Key Claim Terms for Construction

For the ’500 Patent

  • The Term: "nitride film"
  • Context and Importance: The infringement theory for the '500 Patent hinges on an accused Titanium Nitride (TiN) film qualifying as a "nitride film" (Compl. ¶66). Practitioners may focus on this term because the patent specification’s examples are limited to silicon-based nitrides, raising a question of claim scope.
  • Intrinsic Evidence for Interpretation:
    • Evidence for a Broader Interpretation: The claim language itself is broad, simply reciting "nitride film" without specifying its elemental composition. This may support a construction that includes any metallic or non-metallic nitride compound used for its barrier properties.
    • Evidence for a Narrower Interpretation: The specification repeatedly refers to the film as a "silicon nitride film (SiN film, SiON film, or the like)" (U.S. Patent 6,806,500, col. 2:37-39). A party might argue this context limits the claim scope to silicon-based nitride films and their equivalents.

For the ’353 Patent

  • The Term: "lower layer side"
  • Context and Importance: This term defines the required vertical structural relationship between the light-shielding film and the device's wiring. Infringement depends on the accused panel's specific layered construction meeting this limitation.
  • Intrinsic Evidence for Interpretation:
    • Evidence for a Broader Interpretation: The term itself suggests a general positional relationship (i.e., closer to the substrate) rather than a specific manufacturing sequence or direct contact. The complaint's allegation that the film is in "Metal 1" while wires are in "Metal 2" aligns with a broad reading (Compl. ¶91).
    • Evidence for a Narrower Interpretation: A party could argue that the context of the specification, which describes the function of blocking stray light coming from the sides of components, requires a specific spatial arrangement beyond mere layer order to be effective, potentially narrowing the term's construction.

VI. Other Allegations

Indirect Infringement

  • The complaint alleges inducement of infringement by asserting that Sharp sells "Accused Sharp LCD Modules" to third-party customers (e.g., automotive and electronics manufacturers) with knowledge of the patents and the specific intent that those customers will incorporate the modules into infringing end-products sold in the United States (Compl. ¶¶46-49). Contributory infringement is also alleged for the ’606 Patent, claiming the accused modules are a material part of the claimed electronic device and have no substantial non-infringing use (Compl. ¶50).

Willful Infringement

  • The willfulness allegations are based on alleged actual notice provided during multi-year licensing negotiations that began on or around March 1, 2019. The complaint provides specific dates on which notice was allegedly given for each of the asserted patents, contending that Sharp's continued infringement after these dates was deliberate and intentional (Compl. ¶¶35-45).

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

  • A core issue will be one of claim scope and technological evolution: can claim terms from patents with priority dates from the early- to mid-2000s, such as "nitride film" and "dummy area," be construed to cover the specific materials (e.g., TiN) and complex pixel architectures (e.g., multi-transistor layouts) found in modern LCD panels manufactured a decade or more later?
  • A key evidentiary question will be one of structural proof: the complaint's infringement theories rely heavily on detailed reverse engineering of exemplary products. The case may turn on whether the specific, microscopic structures and material compositions alleged in these exemplars are representative of the full range of accused products and whether inferences about unexamined portions of the device (e.g., the "dummy area" structure) can be substantiated.
  • A central question for damages and willfulness will be one of effective notice: did the pre-suit communications during licensing negotiations provide notice that was sufficiently specific as to the patents and accused products to establish the knowledge and intent required for indirect infringement and to render Sharp’s continued conduct willful?