Wuhan China Star Optoelectronics Semiconductor Display Technology Co Ltd v. Samsung Display Co Ltd

I. Executive Summary and Procedural Information

• Parties & Counsel:

  • Plaintiff: Wuhan China Star Optoelectronics Semiconductor Display Technology Co., Ltd. (People's Republic of China)
  • Defendant: Samsung Display Co., Ltd. (Republic of Korea); Walmart Inc. (Delaware); Best Buy Co. Ltd. (Minnesota)
  • Plaintiff's Counsel: Devlin Law Firm LLC

• Case Identification: 2:26-cv-00228, E.D. Tex., 03/24/2026

• Venue Allegations: Venue for Samsung Display is alleged to be proper as it is a foreign corporation subject to personal jurisdiction in the district. Venue for Walmart and Best Buy is alleged based on their numerous regular and established places of business within the Eastern District of Texas and their alleged commission of infringing acts in the district.

• Core Dispute: Plaintiff alleges that OLED display panels manufactured by Defendant Samsung Display, and incorporated into consumer electronics sold by all Defendants, infringe three patents related to the structure, power delivery, and reliability of display panels.

• Technical Context: The technology relates to Organic Light-Emitting Diode (OLED) display panels, which are foundational components for high-end consumer electronics such as flagship and foldable smartphones.

• Key Procedural History: The complaint notes that Defendant Samsung Display has previously filed its own patent infringement lawsuits related to OLED display technology in the same judicial district, suggesting this case may be part of a broader competitive dispute between major industry players.

Case Timeline

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

U.S. Patent No. 12,133,429 - "Display Panel and Display Device," issued October 29, 2024

The Invention Explained

• Problem Addressed: The patent's background section describes an issue in OLED screens where bottom shielding metals, used to protect pixel driving circuits, develop serrated edges when connected to power supply lines. These serrations can act as concentration points for electrical charge, leading to electro-static discharge (ESD) events that damage the panel and degrade the display effect ʼ429 Patent, col. 1:21-34
• The Patented Solution: The invention proposes a specific structural layout for the shielding layer and power lines to mitigate ESD risk. It features a "shielding layer" composed of multiple "shielding blocks" and a "converging wire." Power is delivered from "power supply lines" to this converging wire through a series of "through holes." The key feature is that the segment of the converging wire between any two adjacent through holes is "disposed according to a shortest distance," which the specification describes as being linear. This arrangement is intended to create a more direct and uniform electrical path, preventing the charge accumulation that causes ESD damage ʼ429 Patent, abstract ʼ429 Patent, col. 7:26-34
• Technical Importance: This design aims to enhance the manufacturing yield and long-term reliability of high-resolution OLED panels by addressing a specific electrical failure mode inherent in complex, multi-layered panel architectures.

Key Claims at a Glance

• The complaint asserts at least independent claim 1 Compl. ¶50
• Essential elements of claim 1 include:
  • A substrate.
  • A shielding layer on the substrate comprising a plurality of shielding blocks and a converging wire electrically connected to the shielding blocks.
  • A pixel driving circuit layer located on the shielding layer, with pixel driving circuits at least partially overlapping corresponding shielding blocks.
  • A plurality of power supply lines disposed on a side of the shielding layer away from the substrate and electrically connected to the converging wire through a plurality of through holes.
  • The converging wire between two adjacent through holes is disposed according to a shortest distance between them.
• The complaint does not explicitly reserve the right to assert dependent claims.

U.S. Patent No. 11,957,031 - "Display Device," issued April 9, 2024

The Invention Explained

• Problem Addressed: The patent pertains to flexible OLED displays, particularly those with narrow bezels. To achieve this form factor, certain areas of the display are bent. These bending areas are often covered with UV glues for protection. The problem arises when a final coverplate is attached; the patent states that this process can "squeeze the UV glues, thereby causing the OLED display panels to have a risk of cracking" '031 Patent, col. 2:1-4
• The Patented Solution: The patent discloses a specific multi-layer display structure comprising a flexible screen body, a color filter, a protective layer (e.g., UV glue), and a coverplate. The core of the solution is the requirement that in an overlapping area of the protective layer and the coverplate, the "distance between the protective layer and the coverplate is greater than or equal to a default value," where that default value is explicitly "greater than 0" '031 Patent, abstract This mandated non-zero clearance is designed to prevent the coverplate from exerting mechanical stress on the protective layer and underlying circuits during and after assembly, thus avoiding cracks '031 Patent, col. 7:9-12
• Technical Importance: The invention addresses a critical manufacturing and reliability challenge for flexible and foldable displays, where managing mechanical stress in bent regions is essential for product durability.

Key Claims at a Glance

• The complaint asserts at least independent claim 1 Compl. ¶81
• Essential elements of claim 1 include:
  • A flexible screen body with a planar area and a bending area.
  • A color filter on the flexible screen body covering at least the planar area.
  • A protective layer on the flexible screen body covering at least part of the bending area.
  • A coverplate on the color filter covering at least the planar area.
  • In an overlapping area of the protective layer and the coverplate, a distance between them is greater than or equal to a default value, and the default value is greater than 0.
• The complaint does not explicitly reserve the right to assert dependent claims.

U.S. Patent No. 11,257,891 - "Display Panel," issued February 22, 2022

Technology Synopsis

The patent addresses the challenge of creating display panels with very narrow bottom borders (or "chins"), a key aesthetic and functional goal for modern smartphones '891 Patent, col. 1:31-39 The invention proposes a novel power trace layout where a first power trace is routed around the active display area, while a second power trace is routed between the active area and the bending region. These traces are connected to a component-disposing region via sets of "connecting sub-traces" that pass through the flexible bending region, allowing part of the panel's electronics to be folded behind the screen more efficiently and reducing the visible border '891 Patent, abstract

Asserted Claims

The complaint asserts at least independent claim 1 Compl. ¶112

Accused Features

The complaint alleges that the layout of power traces within the flexible "Accused OLED Display Panels" infringes the patent, particularly in devices marketed for their narrow-bezel designs Compl. ¶¶111-114

III. The Accused Instrumentality

• Product Identification: The primary accused instrumentalities are the "Accused OLED Display Panels" manufactured, imported, and sold by Samsung Display Compl. ¶9 Secondary instrumentalities are the "Accused Products," which are end-user consumer electronics that incorporate these panels, such as smartphones, tablets, and personal wear products Compl. ¶11

• Functionality and Market Context: The complaint identifies specific flagship smartphones, including the Google Pixel 8, 9, and 10 series (including foldable models), as examples of Accused Products Compl. ¶11 Compl. ¶52 Compl. ¶83 The relevant functionality is that of a high-performance, flexible, and in some cases foldable, OLED display. The complaint alleges Samsung Display is a market leader that supplies these panels for high-volume, flagship products with demanding technical requirements Compl. ¶6 Compl. ¶29 The complaint also notes that the Accused OLED Display Panels are distributed through authorized service channels for screen repair and replacement, constituting a separate stream of commerce Compl. ¶¶30-34

IV. Analysis of Infringement Allegations

The complaint references claim charts attached as exhibits that detail the infringement theories for the asserted patents Compl. ¶73 Compl. ¶104 As these exhibits are not provided with the complaint document, the following is a summary of the narrative infringement theories presented in the body of the complaint.

No probative visual evidence provided in complaint.

• '429 Patent Infringement Allegations
  The complaint alleges that the Accused OLED Display Panels contain a layered structure that meets every limitation of claim 1 Compl. ¶49 The infringement theory centers on the allegation that the accused panels include a substrate, a shielding layer with shielding blocks and a converging wire, a pixel driving circuit layer, and power supply lines connected to the converging wire via through-holes. The central factual allegation is that the converging wire in the accused panels is arranged "according to a shortest distance" between adjacent through-holes, thereby literally infringing the patent's key limitation aimed at preventing ESD damage Compl. ¶49

  • Identified Points of Contention:
    • Scope Question: A potential issue may be the construction of the term "shielding block," and whether the structures in the accused panels that Plaintiff identifies as such meet the claim's definition when read in light of the specification.
    • Technical Question: The primary factual dispute may focus on the limitation "disposed according to a shortest distance." The case may turn on what evidence, such as from reverse engineering and microscopy, demonstrates that the physical path of the converging wire in the accused panels meets this precise geometric requirement.

• '031 Patent Infringement Allegations
  The complaint alleges that the Accused Products, particularly those with flexible or foldable screens, embody the claimed display device Compl. ¶80 The theory of infringement is that these devices are constructed with a flexible screen body, a color filter, a protective layer over the bending area, and a coverplate. The crucial allegation is that, in the area where the protective layer and coverplate overlap, a measurable, non-zero distance is maintained between them, satisfying the claim limitation that this distance be "greater than or equal to a default value" where the "default value is greater than 0" Compl. ¶80

  • Identified Points of Contention:
    • Scope Question: The construction of "protective layer" may be a point of contention, particularly whether it is limited to specific materials like UV glue or can encompass other materials used in the bending region of the accused displays.
    • Technical Question: A key evidentiary question will be whether the alleged non-zero distance actually exists in the accused devices. This will likely require detailed cross-sectional analysis of the products to measure the microscopic gaps between layers in the specified overlapping region.

V. Key Claim Terms for Construction

• For the '429 Patent:

  • The Term: "disposed according to a shortest distance" (from claim 1)
  • Context and Importance: This term defines the geometric relationship of the "converging wire" between connection points ("through holes") and is central to the patent's purported solution to ESD. Infringement will hinge on whether the accused panel's wiring conforms to this specific spatial arrangement. Practitioners may focus on this term because it appears to be the primary point of novelty over prior art shielding structures.
  • Intrinsic Evidence for Interpretation:
    • Evidence for a Broader Interpretation: The patent states that the arrangement ensures an "expected current path... is conducted along the shortest distance," which could suggest a functional rather than purely geometric definition, potentially allowing for minor deviations that do not alter the electrical function ʼ429 Patent, col. 7:31-34
    • Evidence for a Narrower Interpretation: The specification explicitly equates this shortest distance to a "virtual line segment 107" shown in the figures as a perfectly straight line between two points ʼ429 Patent, col. 7:26-29 ʼ429 Patent, FIG. 3 This provides strong evidence that the term should be construed narrowly to mean a straight, linear path.

• For the '031 Patent:

  • The Term: "a distance... is greater than or equal to a default value, and wherein the default value is greater than 0" (from claim 1)
  • Context and Importance: This limitation quantifies the core inventive concept of creating a non-zero gap to prevent mechanical stress and cracking. Proving infringement requires demonstrating that the accused device meets this specific condition.
  • Intrinsic Evidence for Interpretation:
    • Evidence for a Broader Interpretation: The patent states the "default value... may be flexibly adjusted according to actual needs, and is not specifically limited in the embodiment," as long as it is greater than zero ʼ031 Patent, col. 6:25-28 This language supports a construction where any measurable, intentional, non-zero gap would satisfy the limitation.
    • Evidence for a Narrower Interpretation: The specification repeatedly links the invention to solving the problem of the coverplate "squeezing" the protective layer and causing cracks (ʼ031 Patent, col. 2:1-4; ʼ031 Patent, col. 7:9-12). A defendant may argue that the term should be construed to require a distance that is functionally significant enough to actually prevent this squeezing phenomenon, not just any incidental or de minimis separation.

VI. Other Allegations

• Indirect Infringement: The complaint alleges both induced and contributory infringement for all asserted patents. Inducement allegations are based on Samsung Display's alleged actions of providing customers (such as Google) and partners with marketing materials, technical specifications, data sheets, and customer support that encourage and instruct on the use of the accused panels in an infringing manner Compl. ¶¶57-64 Compl. ¶¶88-95 Contributory infringement is alleged on the basis that the Accused OLED Display Panels are a material component of the final infringing products, are especially made or adapted for use in an infringing manner, and are not staple articles of commerce suitable for substantial non-infringing use Compl. ¶¶70-72 Compl. ¶¶101-103

• Willful Infringement: Willfulness is alleged based on Defendants' continued infringement after having notice of the patents and the infringement allegations, at least from the filing date of the complaint. The complaint asserts this conduct is knowing, willful, and deliberate, justifying enhanced damages Compl. ¶77 Compl. ¶108 Compl. ¶139

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

• A core issue will be one of geometric correspondence: can the plaintiff provide sufficient evidence, likely through sophisticated reverse engineering, to demonstrate that the physical structure of the accused display panels meets the precise geometric and spatial limitations of the claims, such as the "shortest distance" wiring path of the '429 patent?

• A key evidentiary question will be one of microscopic measurement: does a measurable, non-zero gap, as required by the '031 patent, actually exist between the protective layer and coverplate in the bending region of the accused flexible and foldable devices, and is this feature a result of intentional design or an incidental artifact of manufacturing?

• A central strategic question relates to the competitive context: given that this lawsuit is between major global competitors in the high-stakes OLED market, and that Samsung Display is itself an active patent plaintiff in the same court, the case will likely be viewed as a single front in a larger strategic battle that may ultimately be resolved through business negotiations, such as a cross-licensing agreement, rather than a final verdict.