DCT

6:22-cv-00526

Epistar Corp v. Amazon.com Inc

Log In

I. Executive Summary and Procedural Information

  • Parties & Counsel:
  • Case Identification: 6:22-cv-00526, W.D. Tex., 11/17/2022
  • Venue Allegations: Plaintiff alleges venue is proper in the Western District of Texas because Defendant has committed acts of infringement in the district and maintains a regular and established place of business, specifically a fulfillment center in Waco, Texas.
  • Core Dispute: Plaintiff alleges that light-emitting diode (LED) chips used in Defendant’s Fire TV and Echo product lines infringe thirteen patents related to various aspects of LED structure, fabrication, and performance.
  • Technical Context: The technology concerns the micro-architecture of light-emitting diodes, which are semiconductor devices critical for backlighting in consumer electronics, displays, and general illumination.
  • Key Procedural History: The complaint alleges that Plaintiff first contacted Defendant in 2019 to discuss a potential license for certain patents-in-suit, but Defendant did not respond. Subsequent outreach regarding additional products and patents also allegedly received no response. These events are cited to establish Defendant's pre-suit knowledge of the patents and the alleged infringement.

Case Timeline

Date Event
2007-04-09 Priority Date for U.S. Patent No. 7,705,344
2007-09-07 Priority Date for U.S. Patent No. 7,821,026
2008-12-24 Priority Date for U.S. Patent Nos. 9,257,604; 10,181,549; 10,522,715
2010-04-27 Issue Date for U.S. Patent No. 7,705,344
2010-10-26 Issue Date for U.S. Patent No. 7,821,026
2012-11-02 Priority Date for U.S. Patent Nos. 9,293,656; 9,530,934; 9,893,257; 10,038,129; 10,199,542; 10,505,076
2012-12-26 Priority Date for U.S. Patent No. 8,963,123
2012-12-07 Priority Date for U.S. Patent No. 9,425,362
2015-02-24 Issue Date for U.S. Patent No. 8,963,123
2016-02-09 Issue Date for U.S. Patent No. 9,257,604
2016-03-22 Issue Date for U.S. Patent No. 9,293,656
2016-08-23 Issue Date for U.S. Patent No. 9,425,362
2016-12-27 Issue Date for U.S. Patent No. 9,530,934
2018-02-13 Issue Date for U.S. Patent No. 9,893,257
2018-07-31 Issue Date for U.S. Patent No. 10,038,129
2019-01-15 Issue Date for U.S. Patent No. 10,181,549
2019-02-05 Issue Date for U.S. Patent No. 10,199,542
2019-07-22 Plaintiff allegedly notified Defendant of infringement of certain patents
2019-12-10 Issue Date for U.S. Patent No. 10,505,076
2019-12-31 Issue Date for U.S. Patent No. 10,522,715
2022-02-28 Plaintiff allegedly notified Defendant of infringement of additional patents
2022-11-17 Complaint Filing Date

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

U.S. Patent No. 7,705,344 - “Light-emitting device”

The Invention Explained

  • Problem Addressed: The patent addresses the need to improve the light-emitting efficiency of LEDs that utilize a multi-quantum-well (MQW) active layer structure (’344 Patent, col. 1:30-41; Compl. ¶23).
  • The Patented Solution: The invention proposes a specific n-type doping profile within the MQW active layer. This layer, situated between the primary n-type and p-type semiconductor layers, is partitioned into three distinct regions: one near the n-type layer, one near the p-type layer, and a central region in between. The regions near the n-type and p-type layers are doped, while the central region is either undoped or doped at a lower concentration, a configuration designed to enhance efficiency (’344 Patent, col. 1:53-63; Compl. ¶23).
  • Technical Importance: This structured doping profile is presented as an 'unconventional LED design' capable of improving light output efficiency (’344 Patent, col. 2:8-10; Compl. ¶23).

Key Claims at a Glance

  • The complaint asserts independent claim 1 (Compl. ¶75).
  • Claim 1 requires:
    • An n-type semiconductor layer and a p-type semiconductor layer.
    • An active layer situated between them, comprising a first region, a second region, and a third region positioned between the first and second.
    • Each of these three regions must comprise at least one barrier layer and one well layer.
    • The first and second regions are doped with n-type dopants.
    • The third region is either undoped or doped with n-type dopants at a concentration lower than that in the first and second regions.
  • The complaint reserves the right to modify its infringement contentions, which may suggest an intent to assert additional claims later in the proceedings (Compl. ¶76).

U.S. Patent No. 9,530,934 - “Light-emitting device”

The Invention Explained

  • Problem Addressed: This patent relates generally to the electrode structure of LEDs, with the stated goal of improving device reliability (’934 Patent, Abstract; Compl. ¶27).
  • The Patented Solution: The invention describes a specific geometry for a 'finger electrode' that connects to a larger 'pad electrode.' The key feature is that a portion of the finger electrode comprises a side with a "first arc having a first curvature radius," where that radius is specified to be "larger than 10 µm" (’934 Patent, col. 1:25-34; Compl. ¶27). This specific curvature is intended to prevent current crowding at sharp corners, a common failure point in microelectronics.
  • Technical Importance: This electrode design is described as an "unconventional" approach that improves the reliability of the LED device (’934 Patent, Abstract; Compl. ¶27).

Key Claims at a Glance

  • The complaint asserts independent claim 1 (Compl. ¶81).
  • Claim 1 requires:
    • An LED comprising a finger electrode connected to a pad electrode.
    • The finger electrode includes a first portion extending from the periphery of the pad electrode.
    • This first portion comprises a first side, which in turn comprises a first arc.
    • The first arc has a first curvature radius that is larger than 10 µm.
  • The complaint reserves the right to assert infringement of other claims (Compl. ¶82).

U.S. Patent No. 10,199,542 - “Light-emitting device”

  • Patent Identification: 10,199,542, “Light-emitting device,” issued February 5, 2019 (Compl. ¶29).
  • Technology Synopsis: The patent relates to the electrode structure of LEDs and shares a specification with the ’934 Patent (Compl. ¶30-31). It claims a specific spatial relationship where the shortest distance between a pad electrode and the edge of the semiconductor layer is greater than the shortest distance between a finger electrode and that same edge (Compl. ¶32).
  • Asserted Claims: The complaint asserts independent claim 12 (Compl. ¶88).
  • Accused Features: The complaint alleges the LED chips in Amazon devices embody the claimed electrode geometry (Compl. ¶88-89).

U.S. Patent No. 10,505,076 - “Light-emitting device”

  • Patent Identification: 10,505,076, “Light-emitting device,” issued December 10, 2019 (Compl. ¶33).
  • Technology Synopsis: As a continuation of the application leading to the ’542 Patent, this patent also relates to LED electrode structure (Compl. ¶34-35). It claims, among other features, a finger electrode portion with a width that decreases in a direction away from the pad electrode (Compl. ¶36).
  • Asserted Claims: The complaint asserts independent claim 12 (Compl. ¶95).
  • Accused Features: The complaint alleges the LED chips in Amazon devices contain the claimed tapering finger electrode structure (Compl. ¶95-96).

U.S. Patent No. 9,257,604 - “Light-emitting device having a patterned surface”

  • Patent Identification: 9,257,604, “Light-emitting device having a patterned surface,” issued February 9, 2016 (Compl. ¶37).
  • Technology Synopsis: This patent addresses enhancing light extraction efficiency by creating a patterned surface on the LED's substrate (Compl. ¶38). The claimed pattern unit has a non-polygon shape in a top view and a specific cross-section with a vertex and two inclined line segments (Compl. ¶40).
  • Asserted Claims: The complaint asserts independent claim 1 (Compl. ¶102).
  • Accused Features: The LED chips in the accused devices are alleged to have substrates with the claimed patterned surface to improve light output (Compl. ¶102-103).

U.S. Patent No. 10,181,549 - “Light-emitting device having a patterned surface”

  • Patent Identification: 10,181,549, “Light-emitting device having a patterned surface,” issued January 15, 2019 (Compl. ¶41).
  • Technology Synopsis: Sharing a specification with the ’604 Patent, this patent also relates to patterned surfaces for light extraction (Compl. ¶42-43). It claims a plurality of patterned units that have a circular shape in a top view and comprise two curves with different curvatures in a cross-sectional view (Compl. ¶44).
  • Asserted Claims: The complaint asserts independent claim 1 (Compl. ¶109).
  • Accused Features: The accused LED chips are alleged to have substrates with the claimed circular patterned units (Compl. ¶109-110).

U.S. Patent No. 10,522,715 - “Light-emitting device having a patterned surface”

  • Patent Identification: 10,522,715, “Light-emitting device having a patterned surface,” issued December 31, 2019 (Compl. ¶45).
  • Technology Synopsis: Also in the ’604 patent family, this patent claims patterned surfaces to enhance light extraction (Compl. ¶46-47). The claimed patterned units have a circular shape in a top view and a cross-section with a depth smaller than its width (Compl. ¶48).
  • Asserted Claims: The complaint asserts independent claim 1 (Compl. ¶116).
  • Accused Features: The LED chips in the accused devices are alleged to have the claimed patterned substrate surfaces (Compl. ¶116-117).

U.S. Patent No. 9,293,656 - “Light emitting device”

  • Patent Identification: 9,293,656, “Light emitting device,” issued March 22, 2016 (Compl. ¶49).
  • Technology Synopsis: This patent relates to an efficient electrode structure designed to improve reliability and light emitting efficiency while reducing inter-layer diffusion (Compl. ¶50-51). It claims a barrier layer between a bonding layer and a conductive layer, where the barrier layer comprises alternately stacked metal layers of different materials and thicknesses (Compl. ¶52).
  • Asserted Claims: The complaint asserts independent claim 1 (Compl. ¶123).
  • Accused Features: The electrode structures of the accused LED chips are alleged to contain the claimed multi-layered barrier structure (Compl. ¶123-124).

U.S. Patent No. 9,893,257 - “Electrode structure of light emitting device”

  • Patent Identification: 9,893,257, “Electrode structure of light emitting device,” issued February 13, 2018 (Compl. ¶53).
  • Technology Synopsis: Sharing a specification with the ’656 Patent, this patent also relates to electrode structures (Compl. ¶54-55). It claims a barrier layer with a specific thickness relationship between its constituent metal layers and a non-uniform thickness between its center and edge regions (Compl. ¶56).
  • Asserted Claims: The complaint asserts independent claim 16 (Compl. ¶129).
  • Accused Features: The accused LED chips are alleged to contain electrode structures with the specifically claimed barrier layer features (Compl. ¶129-130).

U.S. Patent No. 10,038,129 - “Light emitting device”

  • Patent Identification: 10,038,129, “Light emitting device,” issued July 31, 2018 (Compl. ¶57).
  • Technology Synopsis: Also in the ’656 patent family, this patent concerns reliable electrode structures (Compl. ¶58-59). It claims specific materials for the barrier layer and specific thickness ratios between the conductive and bonding layers (Compl. ¶60).
  • Asserted Claims: The complaint asserts independent claim 1 (Compl. ¶136).
  • Accused Features: The accused LED chips are alleged to be built with electrode structures meeting the claimed material and thickness ratio limitations (Compl. ¶136-137).

U.S. Patent No. 8,963,123 - “Light emitting diode with enhanced light extraction”

  • Patent Identification: 8,963,123, “Light emitting diode with enhanced light extraction,” issued February 24, 2015 (Compl. ¶61).
  • Technology Synopsis: This patent describes an electrode structure with underlying "light-guiding structures" to enhance light extraction (Compl. ¶62-63). It claims specific dimensional relationships between the light-guiding structures and the finger electrodes above them (Compl. ¶63-64).
  • Asserted Claims: The complaint asserts independent claim 15 (Compl. ¶142).
  • Accused Features: The accused LEDs are alleged to contain the claimed arrangement of finger electrodes and underlying light-guiding structures (Compl. ¶142-143).

U.S. Patent No. 9,425,362 - “Light emitting device”

  • Patent Identification: 9,425,362, “Light emitting device,” issued August 23, 2016 (Compl. ¶65).
  • Technology Synopsis: The patent relates to improving the uniformity of a transparent conductive layer by using a barrier layer with an inclined sidewall at a specific acute angle (10°-70°) (Compl. ¶66-67). This geometry allegedly allows for more uniform coating (Compl. ¶68).
  • Asserted Claims: The complaint asserts independent claim 9 (Compl. ¶148).
  • Accused Features: The accused LED chips are alleged to incorporate a barrier layer with the claimed sidewall angle to achieve uniform coating (Compl. ¶148-149).

U.S. Patent No. 7,821,026 - “Light emitting diode device and manufacturing method thereof”

  • Patent Identification: 7,821,026, “Light emitting diode device and manufacturing method thereof,” issued October 26, 2010 (Compl. ¶69).
  • Technology Synopsis: This patent seeks to provide an LED with low contact resistance and efficient current spreading through a "transparent conductive oxide stack structure" (Compl. ¶70-71). The claimed structure has at least two resistant interfaces and is composed of layers of the same materials but with different composition ratios (Compl. ¶72-73).
  • Asserted Claims: The complaint asserts independent claim 5 (Compl. ¶155).
  • Accused Features: The accused LEDs are alleged to use the claimed transparent conductive oxide stack to manage current and resistance (Compl. ¶155-156).

III. The Accused Instrumentality

Product Identification

The complaint accuses Amazon's Echo devices and Amazon's Fire TV lineup, specifically identifying the 43" and 50" 4-Series and Omni Series televisions (Compl. ¶4-5).

Functionality and Market Context

The accused instrumentalities are consumer electronics that incorporate LED components for illumination. To confirm infringement, the complaint details a tear-down analysis of a 43" 4-Series 4K UHD Amazon Fire TV (Compl. ¶6, ¶9). This analysis revealed three LED backlight strips inside the television's back cover (Compl. ¶9). A photograph in the complaint shows these internal backlight strips (Compl. p. 4, top image). Further disassembly of an individual LED on a strip involved removing a cap lens and a phosphor layer to expose the underlying LED chips, identified as "Light emitting devices" (Compl. ¶11; p. 5, bottom right image). The complaint alleges that these internal LED chips practice the patented inventions.

IV. Analysis of Infringement Allegations

The complaint alleges infringement based on claim chart exhibits (Exhibits A-M) that are referenced but not attached to the complaint itself (Compl. ¶12). Without these exhibits, a detailed element-by-element comparison is not possible from the face of the complaint. The general infringement theory is that the physical structures of the LED chips found within the accused Amazon products, as revealed through tear-down analysis, embody the structures claimed in the patents-in-suit.

  • U.S. Patent No. 7,705,344: The complaint's theory of infringement is that the semiconductor layers of the LED chips within Amazon's products are constructed with the specific three-region active layer and corresponding n-type doping profile recited in claim 1 (Compl. ¶75-76).
  • U.S. Patent No. 9,530,934: The infringement allegation centers on the physical geometry of the electrodes on the accused LED chips. The complaint's theory is that these chips contain a finger electrode with an arc-shaped portion having a curvature radius greater than the 10 µm required by claim 1 (Compl. ¶81-82).
  • Identified Points of Contention:
    • Evidentiary Questions: For many of the patents, including the ’344 Patent, infringement will depend on evidence obtained through sophisticated materials analysis. A central question will be what proof Plaintiff can offer that the accused LED chips possess the specific microscopic doping profiles, layer compositions, and thickness ratios required by the claims.
    • Scope and Measurement Questions: For patents with quantitative geometric limitations, such as the ’934 Patent, a key dispute may arise over claim construction and metrology. The parties may contest how a term like "curvature radius" should be defined and measured on a complex, microscopic electrode, and whether the accused structures meet the claimed "larger than 10 µm" limitation under the correct construction.

V. Key Claim Terms for Construction

  • For the ’344 Patent (Claim 1):

    • The Term: "a concentration lower than that in the first region and that in the second region"
    • Context and Importance: This limitation defines the core of the claimed doping profile. The infringement analysis will depend on whether the concentration of n-type dopants in the central region of the accused device's active layer is measurably "lower than" the concentrations in the outer regions. Practitioners may focus on this term because the functionality of the invention is tied to this relative difference.
    • Intrinsic Evidence for Interpretation:
      • Evidence for a Broader Interpretation: The claim language itself does not require a specific numerical difference, potentially supporting a construction where any statistically significant lower concentration meets the limitation.
      • Evidence for a Narrower Interpretation: The specification discloses that the third region can be "undoped" (’344 Patent, col. 1:58-63; Compl. ¶23), which a defendant may argue suggests that "lower concentration" should be construed to mean substantially lower or approaching zero, rather than a minor variation.

  • For the ’934 Patent (Claim 1):

    • The Term: "curvature radius"
    • Context and Importance: The infringement determination for this patent hinges on a quantitative measurement: whether the "curvature radius" of the accused electrode's "first arc" is "larger than 10 µm." The definition of this term will be critical. Practitioners may focus on this term because its construction will determine the methodology for measuring the accused device and comparing it to the claim.
    • Intrinsic Evidence for Interpretation:
      • Evidence for a Broader Interpretation: If the patent does not provide an explicit definition, a party may argue for the term's plain and ordinary meaning as understood by a person of ordinary skill in the art of semiconductor design, which could allow for various geometric approximation methods.
      • Evidence for a Narrower Interpretation: The patent figures may depict the "arc" as a segment of a perfect circle, which would support a narrower construction where the "curvature radius" must be determined by fitting a circle to the feature, as opposed to other mathematical methods for calculating curvature.

VI. Other Allegations

  • Indirect Infringement: The complaint alleges induced infringement for all thirteen patents. The factual basis for inducement is that Defendant allegedly promotes, advertises, and provides product literature that instructs and encourages end-users to use the accused Amazon devices in their normal, infringing manner (e.g., Compl. ¶77, ¶84, ¶91).
  • Willful Infringement: The complaint alleges that Defendant had actual knowledge of numerous patents-in-suit prior to the litigation, based on correspondence sent on July 22, 2019, and February 28, 2022 (e.g., Compl. ¶83, ¶90, ¶104). For other patents, knowledge is alleged from at least the date of the complaint filing. This combination of alleged pre-suit and post-suit knowledge forms the basis for the willfulness allegations.

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

This case presents a broad challenge to the LED components within a major portfolio of consumer electronics. The litigation will likely focus on a few central issues:

  • A core issue will be one of evidentiary proof: Can the Plaintiff, through reverse engineering and expert testimony, produce definitive evidence that the microscopic and material properties of the accused LED chips—such as the specific doping profiles claimed in the ’344 patent or the alternately stacked metal layers of the ’656 patent—meet the precise limitations of the asserted claims?
  • A key legal question will be one of claim scope and metrology: For patents with quantitative limitations, such as the ’934 patent's requirement of a "curvature radius...larger than 10 µm," the dispute will likely involve claim construction. The case may turn on how such terms are defined and whether the chosen measurement methodology for the accused products is appropriate under that definition.
  • A significant procedural question will be one of case management and redundancy: With thirteen asserted patents, many of which belong to the same families and cover similar subject matter (e.g., patterned substrates, electrode structures), a central challenge for the parties and the court will be to manage the complexity. This could lead to disputes over claim differentiation, the selection of representative claims for trial, and potential invalidity challenges based on overlapping disclosures.