DCT
2:19-cv-06570
Regents Of University Of California v. Walmart Inc
I. Executive Summary and Procedural Information
- Parties & Counsel:
- Plaintiff: The Regents of the University of California (California)
- Defendant: Walmart Inc. (Delaware)
- Plaintiff’s Counsel: Nixon Peabody LLP
- Case Identification: 2:19-cv-06570, C.D. Cal., 07/30/2019
- Venue Allegations: Venue is alleged to be proper based on Defendant operating numerous regular and established retail store locations throughout the Central District of California where infringing sales have occurred.
- Core Dispute: Plaintiff alleges that Defendant’s filament LED light bulbs infringe four patents related to foundational LED technology for improving light extraction and efficiency.
- Technical Context: The technology at issue is filament-style Light Emitting Diode (LED) bulbs, an energy-efficient lighting category designed to aesthetically replicate traditional incandescent bulbs.
- Key Procedural History: The complaint alleges that Plaintiff provided Defendant with notice of infringement for U.S. Patent Nos. 7,781,789 and 9,240,529 via a certified letter dated December 20, 2017. The front pages of the Asserted Patents indicate that after this complaint was filed, Inter Partes Review (IPR) proceedings were initiated against all four patents, resulting in the cancellation of numerous claims.
Case Timeline
| Date | Event |
|---|---|
| 2006-11-15 | Earliest Priority Date (’789, ’529, ’464 Patents) |
| 2006-12-11 | Earliest Priority Date (’916 Patent) |
| 2010-08-24 | ’789 Patent Issued |
| 2014-01-01 | Filament LED bulbs become widely available in U.S. (approx. date) |
| 2016-01-19 | ’529 Patent Issued |
| 2017-12-20 | Plaintiff sends notice letter to Defendant regarding ’789 and ’529 Patents |
| 2018-01-02 | ’464 Patent Issued |
| 2019-02-26 | ’916 Patent Issued |
| 2019-06-24 | Plaintiff purchases accused product at a Walmart in Burbank, CA |
| 2019-07-30 | Complaint Filed |
II. Technology and Patent(s)-in-Suit Analysis
U.S. Patent No. 7,781,789 - "Transparent Mirrorless Light Emitting Diode"
The Invention Explained
- Problem Addressed: The patent’s background describes that in conventional LEDs, light is often reflected by a mirror on the backside of the device; however, this reflected light can be re-absorbed by the active light-emitting layer, which decreases the device’s overall efficiency and light output (ʼ789 Patent, col. 1:47-62).
- The Patented Solution: The invention proposes a "transparent mirrorless" LED structure where mirrors are eliminated to minimize internal reflections and re-absorption (ʼ789 Patent, col. 2:13-26). The design uses transparent layers to allow light to be extracted from multiple sides of the LED chip, thereby increasing efficiency (ʼ789 Patent, Abstract; Fig. 4A).
- Technical Importance: This approach seeks to improve the fundamental light extraction efficiency of an LED device by reducing a key source of internal energy loss.
Key Claims at a Glance
- The complaint asserts infringement of "at least one claim" of the ’789 Patent (Compl. ¶46). The complaint references an Exhibit G containing a claim chart, but this exhibit was not attached to the publicly filed complaint. Independent claim 1 is representative:
- An opto-electronic device, comprising:
- a light emitting diode (LED) that emits light out of the LED from multiple sides of the LED,
- wherein all layers of the LED are transparent for an emission wavelength except for an emitting layer.
- The complaint reserves the right to assert additional claims (Compl. ¶47).
U.S. Patent No. 9,240,529 - "Textured Phosphor Conversion Layer Light Emitting Diode"
The Invention Explained
- Problem Addressed: In white LEDs that use a phosphor layer to convert blue light to other colors, a significant portion of the converted light is reflected at the smooth surface of the phosphor layer back toward the LED chip, where it is re-absorbed, reducing the device's luminous efficacy (ʼ529 Patent, col. 5:14-25).
- The Patented Solution: The invention solves this by texturing, patterning, or shaping the surface of the phosphor layer (ʼ529 Patent, Abstract). This non-planar surface reduces internal reflection and allows more of the converted light to escape the device, as illustrated by the pyramid-like surface texturing (108) shown in Figure 1 of the patent (ʼ529 Patent, Fig. 1; col. 6:8-12).
- Technical Importance: This innovation provides a method to increase the energy efficiency of phosphor-converted white LEDs, a dominant technology for solid-state general illumination.
Key Claims at a Glance
- The complaint asserts infringement of "at least one claim" of the ’529 Patent (Compl. ¶50). The complaint references an Exhibit H containing a claim chart, but this exhibit was not attached to the publicly filed complaint. Independent claim 1 is representative:
- A light emitting device, comprising:
- an LED chip emitting light at a first wavelength region;
- an encapsulation layer, coupled to the LED chip...transparent at the first wavelength region;
- a phosphor layer, coupled to the encapsulation layer and distant from the LED chip;
- the phosphor layer converting the light...to light in at least a second wavelength region;
- wherein at least a portion of a surface of the phosphor layer is textured.
- The complaint reserves the right to assert additional claims (Compl. ¶51).
U.S. Patent No. 9,859,464 - "Light Emitting Diode With Light Extracted From Front And Back Sides Of A Lead Frame"
- Technology Synopsis: The patent describes an LED device wherein the LED chip is mounted on a lead frame that incorporates a transparent plate. This structure is designed to allow light to be extracted from both the front and back sides of the device, passing through the transparent plate to increase total light output (’464 Patent, Abstract).
- Asserted Claims: At least one claim is asserted (Compl. ¶54). Claim 1 is the sole independent claim.
- Accused Features: The filament LED bulbs are accused of infringing by allegedly incorporating a structure where light is emitted from multiple sides of the LED components mounted on a lead frame (Compl. ¶¶ 42, 55).
U.S. Patent No. 10,217,916 - "Transparent Light Emitting Diodes"
- Technology Synopsis: The patent discloses a transparent LED structure made of III-nitride layers, where all layers are transparent to the emitted light except for the active region itself. The specification describes that the surfaces of these layers can be textured, patterned, or shaped to enhance the amount of light that escapes the device in multiple directions (’916 Patent, Abstract).
- Asserted Claims: At least one claim is asserted (Compl. ¶58). Representative independent claims include 13 and 14.
- Accused Features: The accused filament LED bulbs are alleged to embody a transparent structure allowing multi-directional light emission, consistent with the patent's teachings (Compl. ¶¶ 42, 59).
III. The Accused Instrumentality
Product Identification
The accused products are "filament LED light bulbs," including specific models sold under the "Great Value" and "Sylvania" brands at Walmart stores (Compl. ¶¶ 9, 42). A representative product identified is the "Great Value LED Deco Vintage Edison Light Bulb 4w Deco 2pk (Model: CAD4W22G-2P)" (Compl. ¶¶ 18, 42).
Functionality and Market Context
The accused products are designed as energy-efficient replacements for traditional incandescent light bulbs, specifically mimicking the aesthetic of "Edison" or "vintage" bulbs with visible, glowing filaments (Compl. ¶12). An image in the complaint depicts a "Filament LED Light Bulb," showing multiple linear LED filaments arranged within a clear glass bulb (Compl. p. 2). The complaint alleges that these products are aesthetically pleasing and offer significant energy savings over their lifespan (Compl. ¶¶ 14-15). The packaging for an accused Great Value product, for example, claims savings of up to $184 over a 13-year life (Compl. ¶19; p. 5, Image). The U.S. market for these products was expected to exceed $1 billion in 2019 (Compl. ¶16).
IV. Analysis of Infringement Allegations
The complaint alleges infringement is demonstrated in claim chart exhibits, which were not attached to the publicly filed complaint. The following summary is based on the narrative allegations.
’789 Patent Infringement Allegations
| Claim Element (from Independent Claim 1) | Alleged Infringing Functionality | Complaint Citation | Patent Citation |
|---|---|---|---|
| a light emitting diode (LED) that emits light out of the LED from multiple sides of the LED | The accused filament LED bulbs are constructed with visible filaments in a clear bulb, a design that inherently provides omnidirectional light emission. | ¶8, ¶15 | col. 2:13-20 |
| wherein all layers of the LED are transparent for an emission wavelength except for an emitting layer | The filament LED structure is necessarily transparent to allow the "glowing filaments" to be visible, thereby allegedly meeting the transparency requirement. | ¶12 | col. 2:13-20 |
’529 Patent Infringement Allegations
| Claim Element (from Independent Claim 1) | Alleged Infringing Functionality | Complaint Citation | Patent Citation |
|---|---|---|---|
| a phosphor layer, coupled to the encapsulation layer and distant from the LED chip | In filament LEDs, the phosphor is typically coated onto a substrate to form the "filament," which is physically separate and therefore distant from the blue LED dies that excite it. | p. 2, Image | col. 5:26-30 |
| wherein at least a portion of a surface of the phosphor layer is textured | The complaint does not contain specific factual allegations detailing how the phosphor layer of the accused products is "textured." | ¶50 | col. 6:8-12 |
Identified Points of Contention
- Scope Questions:
- For the ’789 Patent, a central question may be whether the term "multiple sides of the LED," as defined by a specification that illustrates emission from opposite faces of a semiconductor die, can be construed to read on the omnidirectional light pattern of a packaged filament bulb assembly.
- For the ’529 Patent, the interpretation of "distant from the LED chip" will be at issue. The dispute may center on whether a phosphor coating on a substrate that also holds the LED dies meets the claimed "distant" relationship.
- Technical Questions:
- The complaint's infringement theory for the ’529 Patent raises the evidentiary question of whether the phosphor layers on the accused products are in fact "textured" as required by the claims. The analysis will depend on whether incidental surface roughness from the manufacturing process meets the claim limitation, or if an intentional, engineered topography is required.
V. Key Claim Terms for Construction
"multiple sides of the LED" (’789 Patent, Claim 1)
- Context and Importance: This term's construction is critical for determining infringement. If construed narrowly to mean opposing faces of the semiconductor chip itself, infringement may be more difficult to establish for a packaged filament bulb. If construed broadly to mean the overall light emission pattern of the packaged device, the infringement argument may be strengthened.
- Intrinsic Evidence for Interpretation:
- Evidence for a Broader Interpretation: The abstract states the invention allows light to be "extracted effectively... in multiple directions," which may support a construction focused on the overall emission characteristics rather than specific chip surfaces (’789 Patent, Abstract).
- Evidence for a Narrower Interpretation: Figures in the patent, such as Figure 4A, explicitly depict a semiconductor structure with light exiting opposite surfaces (412 and 414), which could support a narrower construction limited to the die itself (’789 Patent, Fig. 4A).
"textured" (’529 Patent, Claim 1)
- Context and Importance: This term is the core inventive concept of the asserted ’529 patent claim. Its definition will determine the scope of infringing articles. Practitioners may focus on this term because the complaint does not specify how the accused products meet this limitation.
- Intrinsic Evidence for Interpretation:
- Evidence for a Broader Interpretation: The specification describes a method of creating the texture by curing the phosphor resin on sandpaper, suggesting that a generally non-planar or rough surface, rather than a precisely repeating pattern, could fall within the term's scope (’529 Patent, col. 6:1-4).
- Evidence for a Narrower Interpretation: The patent repeatedly uses the phrase "textured, patterned, or shaped," which may imply that "textured" refers to an intentional surface modification, not incidental roughness. Figure 1 depicts a regular, pyramid-like surface (108), which could support a construction requiring an engineered, non-random topography (’529 Patent, Fig. 1).
VI. Other Allegations
Indirect Infringement
The complaint alleges infringement under 35 U.S.C. § 271(g) for the importation of products made abroad by a patented process (Compl. ¶¶ 46, 50, 54, 58). This is supported by allegations that the accused products are made by "unlicensed foreign manufacturers" and labeled "Made in China" (Compl. ¶¶ 10, 44). The complaint does not plead specific counts for inducement or contributory infringement.
Willful Infringement
The complaint alleges pre-suit knowledge of the ’789 and ’529 patents based on Defendant's receipt of a notice letter on December 26, 2017 (Compl. ¶41). For the ’464 and ’916 patents, which issued after this letter, knowledge is premised on the filing of the lawsuit, which would support a claim for post-suit willfulness.
VII. Analyst’s Conclusion: Key Questions for the Case
This case, as originally filed, presents several fundamental questions of claim scope and evidentiary proof. The subsequent invalidation of numerous claims in IPR proceedings introduces a threshold question about the ongoing viability of the suit itself. Based on the initial complaint, the key issues would be:
- A core issue will be one of definitional scope: Can terms like "multiple sides" and "transparent," which are described in the context of a semiconductor die in the ’789 patent, be construed to read on the macro-level characteristics of a commercially packaged filament LED bulb?
- A key evidentiary question will be one of technical proof: What evidence exists that the phosphor layer on the accused filaments is "textured" in a manner consistent with the claims and specification of the ’529 patent, or is there a mismatch between the patent's requirement for an engineered surface and the reality of the accused products?
- A central procedural question will be the impact of post-filing events: How will the cancellation of numerous patent claims in subsequent IPRs affect which, if any, of the Plaintiff's infringement theories can proceed, and to what extent must the case be narrowed or amended in light of those administrative outcomes?