DCT
1:21-cv-05021
Lyne Laboratories Inc v. Home Depot Inc
I. Executive Summary and Procedural Information
- Parties & Counsel:
- Plaintiff: Lynk Labs, Inc. (Illinois)
- Defendant: Home Depot USA, Inc., The Home Depot Inc., and Home Depot Product Authority, LLC (Delaware, Georgia)
- Plaintiff’s Counsel: K&L GATES LLP
- Case Identification: 6:21-cv-00097, W.D. Tex., 03/17/2021
- Venue Allegations: Venue is alleged based on Defendants' operation of retail stores, distribution centers, a technology center, and an innovation lab within the Western District of Texas, as well as the sale of accused products in the district.
- Core Dispute: Plaintiff alleges that Defendant’s private label LED lighting products infringe nine patents related to AC LED drive methods, driver-on-board configurations, and user-selectable color temperature and brightness technologies.
- Technical Context: The technology concerns methods for efficiently powering and controlling Light Emitting Diodes (LEDs) with alternating current (AC) power, a foundational technology in the modern general lighting market.
- Key Procedural History: The complaint alleges extensive pre-suit communications beginning in January 2018, during which Plaintiff presented its patent portfolio to Defendant and identified allegedly infringing products. Subsequent Inter Partes Review (IPR) and Post-Grant Review (PGR) proceedings, concluded after the filing of this complaint, resulted in the cancellation or disclaimer of nearly all asserted claims across the nine patents-in-suit. This development fundamentally alters the landscape of the dispute, as the legal viability of most of the infringement contentions in the complaint has been extinguished.
Case Timeline
| Date | Event |
|---|---|
| 1997-01-01 | Lynk Labs founded |
| 2010-05-12 | Earliest Priority Date for '251, '842, '979, '551, '149 Patents |
| 2011-12-02 | Earliest Priority Date for '783, '479 Patents |
| 2015-11-10 | Earliest Priority Date for '341, '001 Patents |
| 2018-01-04 | Plaintiff presents patent portfolio to Defendant |
| 2018-10-02 | U.S. Patent No. 10,091,842 ('842 Patent) issues |
| 2018-12-11 | U.S. Patent No. 10,154,551 ('551 Patent) issues |
| 2019-07-09 | U.S. Patent No. 10,349,479 ('479 Patent) issues |
| 2019-11-26 | U.S. Patent No. 10,492,251 ('251 Patent) issues |
| 2019-12-24 | U.S. Patent No. 10,517,149 ('149 Patent) issues |
| 2020-01-14 | U.S. Patent No. 10,537,001 ('001 Patent) issues |
| 2020-03-05 | Plaintiff provides further notice of infringement to Defendant |
| 2020-04-29 | Plaintiff provides further notice of infringement to Defendant |
| 2020-05-12 | U.S. Patent No. 10,652,979 ('979 Patent) issues |
| 2020-07-24 | Plaintiff notifies Defendant of allowed application for '783 Patent |
| 2020-08-25 | U.S. Patent No. 10,757,783 ('783 Patent) issues |
| 2021-01-12 | Plaintiff notifies Defendant of allowed application for '341 Patent |
| 2021-02-23 | U.S. Patent No. 10,932,341 ('341 Patent) issues |
| 2021-03-17 | Complaint filed |
II. Technology and Patent(s)-in-Suit Analysis
U.S. Patent No. 10,492,251 - AC Light Emitting Diode and AC LED Drive Methods and Apparatus
- Patent Identification: U.S. Patent No. 10,492,251, "AC Light Emitting Diode and AC LED Drive Methods and Apparatus," issued November 26, 2019. (Compl. ¶54).
The Invention Explained
- Problem Addressed: The patent's background describes the technical challenge of powering Light Emitting Diodes (LEDs)—which are intrinsically direct current (DC) devices—with an alternating current (AC) power source, a task that traditionally required bulky and inefficient transformers and rectifiers. (US10492251B2, col. 1:47-2:14).
- The Patented Solution: The invention proposes LED circuits that can be driven directly by AC power. A central concept is an LED driver that receives a standard AC voltage at a first frequency (e.g., 60 Hz) and provides a higher frequency output to an array of LED circuits. ('251 Patent, Abstract). This approach can be used to power multiple LED circuits that may have different color characteristics, allowing for features like selectable color temperature. ('251 Patent, col. 4:55-5:4).
- Technical Importance: This technology aimed to simplify the design of LED lighting systems by reducing the need for complex power conversion components, thereby enabling more compact, efficient, and feature-rich products like those with user-selectable color output. (Compl. ¶¶23, 39).
Key Claims at a Glance
- The complaint asserts independent claims 11 and 13. (Compl. ¶¶65, 67).
- Claim 11 requires, in brief:
- An LED lighting system with an LED circuit array having a plurality of LED circuits.
- An active current limiting device connected in series with at least one of the LED circuits.
- An LED driver with an AC input at a first frequency and an output at a second, relatively higher frequency.
- At least one LED in one circuit is coated or doped to produce a different color of light than an LED in another circuit.
- Claim 13 requires, in brief:
- A lighting system with a driver that includes a bridge rectifier.
- The driver receives an input voltage from a mains power source.
- At least one LED circuit mounted on a reflective substrate is connected to the driver's output.
- The LED circuit has LEDs connected to approximately match the input or output voltage of the driver.
U.S. Patent No. 10,757,783 - Color Temperature Controlled and Low THD LED Lighting Devices and Systems and Methods of Driving the Same
- Patent Identification: U.S. Patent No. 10,757,783, "Color Temperature Controlled and Low THD LED Lighting Devices and Systems and Methods of Driving the Same," issued August 25, 2020. (Compl. ¶55).
The Invention Explained
- Problem Addressed: The patent identifies a market desire for LED lighting that can change color temperature (e.g., from a "warm" yellow-white to a "cool" blue-white), a feature common in dimming incandescent bulbs but historically complex and costly to implement in LEDs. The patent also notes the goals of improving power factor and reducing total harmonic distortion (THD) in AC-driven LEDs. ('783 Patent, col. 2:4-21).
- The Patented Solution: The invention describes an LED lighting device with at least two LED circuits, each configured to emit light of a different color temperature. The device includes a switch that enables a user to select which color temperature is emitted. The circuits and switch are integrated onto a single substrate and driven by an AC voltage source. ('783 Patent, Abstract; col. 4:45-5:2).
- Technical Importance: This approach provided a simplified and economical method for incorporating user-selectable color temperature into a single LED fixture, a feature that enhances consumer appeal and product versatility. (Compl. ¶39).
Key Claims at a Glance
- The complaint asserts independent claims 1, 8, and 17. (Compl. ¶80).
- Claim 8 requires, in brief:
- An LED lighting device with at least one LED circuit having at least two LEDs.
- An LED is configured to emit a different color temperature than at least one other LED.
- A switch is configured for user selection of the different color temperatures.
- The LED circuit and switch are integrated into the device, which is driven by an AC voltage source.
- The LED circuit and LEDs are integrated on a single substrate.
Multi-Patent Capsule: U.S. Patent No. 10,091,842
- Patent Identification: U.S. Patent No. 10,091,842, "AC Light Emitting Diode and AC LED Drive Methods and Apparatus," issued October 2, 2018. (Compl. ¶56).
- Technology Synopsis: This patent relates to LED lighting systems with multiple distinct LED circuits. It describes a driver that receives an AC input and provides a rectified DC or rectified AC output at a higher frequency to power the different LED circuits, which can be connected in parallel one at a time. ('842 Patent, col. 21:1-22:22).
- Asserted Claims: 33, 38, and 43. (Compl. ¶93).
- Accused Features: The complaint alleges that products with user-selectable Correlated Color Temperature (CCT) technology, such as the Commercial Electric Spin Light, infringe this patent. (Compl. ¶94).
Multi-Patent Capsule: U.S. Patent No. 10,932,341
- Patent Identification: U.S. Patent No. 10,932,341, "Multi-voltage and multi-brightness LED lighting devices and methods of using same," issued February 23, 2021. (Compl. ¶57).
- Technology Synopsis: This patent describes an LED lighting device with at least two LED circuits, where one is a "first operating" circuit and the other is an "additional" circuit. A user-selectable switch can turn the additional circuit on or off, or change the brightness level of one of the circuits, allowing for multi-brightness or multi-color functionality from an AC power source. ('341 Patent, col. 11:51-12:5).
- Asserted Claims: 1. (Compl. ¶106).
- Accused Features: Products with selectable color temperature, such as the Commercial Electric Spin Light, are accused of infringement. (Compl. ¶107).
Multi-Patent Capsule: U.S. Patent No. 10,537,001
- Patent Identification: U.S. Patent No. 10,537,001, "Multi-voltage and Multi-brightness LED Lighting Devices and Methods of Using Same," issued January 14, 2020. (Compl. ¶58).
- Technology Synopsis: This patent is directed to an LED lighting device with a first operating LED circuit and at least one additional LED circuit. The invention includes a user-selectable switch to independently turn the circuits on or off, or to adjust their brightness, and a driver that has an output voltage lower than the AC mains input voltage but at a higher frequency. ('001 Patent, col. 11:55-12:8).
- Asserted Claims: 1, 6, 11, and 16. (Compl. ¶119).
- Accused Features: Products with selectable color temperature, such as the Commercial Electric 13 in. Brushed Nickel Color Changing LED Ceiling Flush Mount, are accused of infringement. (Compl. ¶120).
Multi-Patent Capsule: U.S. Patent No. 10,349,479
- Patent Identification: U.S. Patent No. 10,349,479, "Color Temperature Controlled and Low THD LED Lighting Devices and Systems and Methods of Driving the Same," issued July 9, 2019. (Compl. ¶59).
- Technology Synopsis: This patent describes an LED lighting system with two switches. A first switch controls the amount of voltage or current to control brightness, and a second switch allows disconnecting a first LED circuit and connecting a second LED circuit to the AC voltage source, enabling features like color selection or warm-dim effects. ('479 Patent, col. 19:8-21).
- Asserted Claims: 2 and 9. (Compl. ¶132).
- Accused Features: Products with both dimmable and color-selectable features, like the Commercial Electric 13 in. Brushed Nickel Color Changing LED Ceiling Flush Mount, are accused of infringement. (Compl. ¶133).
Multi-Patent Capsule: U.S. Patent No. 10,652,979
- Patent Identification: U.S. Patent No. 10,652,979, "LED Lighting System," issued May 12, 2020. (Compl. ¶60).
- Technology Synopsis: This patent describes a "Driver-on-Board" (DoB) technology where the lighting device connects directly to a mains AC power source. The system includes an LED circuit with LEDs connected in series to match the forward voltage drop of the AC source, and an LED driver circuit with a driver IC, bridge rectifier, and capacitor, all mounted on a single insulating substrate. ('979 Patent, col. 1:50-2:6).
- Asserted Claims: 7. (Compl. ¶145).
- Accused Features: The complaint alleges that products featuring DoB technology, such as the EcoSmart 6 in. White Integrated LED Recessed Trim, infringe this patent. (Compl. ¶146).
Multi-Patent Capsule: U.S. Patent No. 10,154,551
- Patent Identification: U.S. Patent No. 10,154,551, "AC Light Emitting Diode and AC LED Drive Methods and Apparatus," issued December 11, 2018. (Compl. ¶61).
- Technology Synopsis: This patent is directed to an LED lighting system where the driver, bridge rectifier, at least one capacitor, and the LED circuit are all mounted on a single reflective substrate. The driver receives a rectified AC voltage from a mains power source and provides it to the LED circuit. ('551 Patent, col. 23:1-12).
- Asserted Claims: 1 and 5. (Compl. ¶158).
- Accused Features: Products featuring DoB technology, such as the EcoSmart 6 in. White Integrated LED Recessed Trim, are accused of infringement. (Compl. ¶159).
Multi-Patent Capsule: U.S. Patent No. 10,517,149
- Patent Identification: U.S. Patent No. 10,517,149, "AC Light Emitting Diode and AC LED Drive Methods and Apparatus," issued December 24, 2019. (Compl. ¶62).
- Technology Synopsis: This patent describes an "Integrated Driver" technology. The system includes an LED circuit, a driver with at least one transistor and capacitor, and a heat-sinking reflective package, with the driver and LED circuit mounted on the package. The driver is configured to receive AC voltage from a mains power source. ('149 Patent, col. 23:1-20).
- Asserted Claims: 1. (Compl. ¶171).
- Accused Features: Products featuring "Integrated Driver technology," such as the EcoSmart 6 in. White Integrated LED Recessed Trim, are accused of infringement. (Compl. ¶172).
III. The Accused Instrumentality
Product Identification
- The complaint accuses numerous private label LED lighting products sold by HOME DEPOT under the brands Commercial Electric, Hampton Bay, EcoSmart, and Home Decorators Collection. (Compl. ¶¶65, 67, 80). Exemplary products include the "Commercial Electric Spin Light 7 in. White Selectable LED Flush Mount" (SKU: 1002 312 164) and the "EcoSmart 6 in. White Integrated LED Recessed Trim" (SKU: 1002 936 719). (Compl. ¶¶66, 68, 81).
Functionality and Market Context
- The accused products are alleged to incorporate two key technologies from the patents-in-suit: (1) Correlated Color Temperature (CCT) selectable technology, which allows a user to select the color of light output (e.g., soft white, bright white, daylight) via an integrated switch, and (2) Driver-on-Board (DoB) or Integrated Driver technology, where the electronic driver components are mounted on the same circuit board as the LEDs. (Compl. ¶¶66, 68, 81). The complaint provides a photograph of product packaging for the Commercial Electric "Customizable Recessed Trim" which advertises "5 White Color Options" and "3 Brightness Levels" selectable via an "Integrated Switch". (Compl. p. 18). The complaint alleges these products are part of an expansion of Home Depot's private label brands that has increased its profits "at the expense of the lighting industry." (Compl. ¶28).
IV. Analysis of Infringement Allegations
’251 Patent Infringement Allegations
| Claim Element (from Independent Claim 11) | Alleged Infringing Functionality | Complaint Citation | Patent Citation |
|---|---|---|---|
| an LED lighting system comprising: an LED circuit array having a plurality of LED circuits, each LED circuit of the plurality of LED circuits comprising at least one LED; | The Commercial Electric Spin Light product contains a circuit board with multiple distinct circuits of LEDs. | ¶66 | col. 21:1-4 |
| an active current limiting device connected in series to at least one of the plurality of LED circuits; | The complaint does not provide sufficient detail for analysis of this element. | ¶66 | col. 21:5-7 |
| an LED driver connected to the LED circuit array, wherein the LED driver has an input of a first voltage and a first frequency and provides an output of a second voltage, wherein the first voltage is an AC voltage; | The product's driver receives 120 VAC from a socket connector. A photograph shows a component labeled "Driver" on the circuit board connected to the LED array. | ¶66; p. 23 | col. 21:8-13 |
| wherein an LED of at least one of the plurality of LED circuits in the LED circuit array is coated or doped with at least one of a phosphor, nano-crystals, or a light changing or enhancing substance, at least one of the coated or doped LEDs in the LED circuit array producing a different color of light than another coated or doped LED in the LED circuit array. | The product has two sets of LEDs, labeled "LEDs (color 1)" and "LEDs (color 2)," which allegedly produce different colors of light to enable the CCT-selectable feature. | ¶66; p. 23 | col. 21:14-22 |
’251 Patent Infringement Allegations
| Claim Element (from Independent Claim 13) | Alleged Infringing Functionality | Complaint Citation | Patent Citation |
|---|---|---|---|
| a lighting system, comprising: a driver having an input and an output, the input receiving an input voltage from a mains power source and the output providing an output voltage, wherein the driver includes a bridge rectifier; | The EcoSmart Recessed Trim has a driver that connects to a mains power source. A photograph identifies a "Bridge Rectifier" as part of the driver circuitry on the board. | ¶68; p. 28 | col. 22:23-29 |
| and at least one LED circuit mounted on a reflective substrate, wherein the at least one LED circuit is connected to the output of the driver and has one or more LEDs connected in series or parallel sufficient to approximately match the input voltage or the output voltage of the driver. | The product has an LED circuit mounted on a board labeled "Reflective Substrate." The LEDs are connected to the driver's output and are arranged to operate with the voltage provided by the driver. | ¶68; p. 28 | col. 22:30-36 |
’783 Patent Infringement Allegations
| Claim Element (from Independent Claim 8) | Alleged Infringing Functionality | Complaint Citation | Patent Citation |
|---|---|---|---|
| at least one LED circuit having at least two LEDs, an LED of the at least two LEDs being configured to emit light of a different color temperature than at least one other LED of the at least two LEDs; | The Commercial Electric Spin Light contains an LED circuit with two sets of LEDs, labeled "LEDs (color 1)" and "LEDs (color 2)," which produce different color temperatures. | ¶81; p. 35 | col. 23:40-44 |
| and a switch configured to enable user selection of the different color temperatures of light to be emitted by the at least one LED circuit; | The product contains a physical toggle switch on the device housing that allows a user to select between 3000K, 4000K, and 5000K color outputs. An instructional diagram shows this "Switch for color choice." | ¶81; p. 35, 36 | col. 23:45-48 |
| wherein the color temperature is produced by at least one of the at least two LEDs, | The different color temperatures are produced by activating one or more of the two sets of LEDs on the circuit. | ¶81 | col. 23:49-50 |
| wherein the at least one LED circuit and the switch are integrated into the LED lighting device, | The switch and the LED circuit are both physically integrated into the housing of the lighting fixture. | ¶81; p. 35 | col. 23:51-53 |
| wherein the LED lighting device is driven with an AC voltage source, and | The device is configured to connect to a 120 VAC socket connector, which is an AC voltage source. | ¶81; p. 35 | col. 23:54-55 |
| wherein the at least one LED circuit and the at least two LEDs are integrated on a single substrate. | The two sets of LEDs comprising the LED circuit are mounted on a single printed circuit board, identified as the "Substrate." | ¶81; p. 35 | col. 23:56-58 |
Identified Points of Contention
- Scope Questions: A primary question for the '783 Patent may be whether the term "switch configured to enable user selection" encompasses a switch on the fixture body that is typically set once at installation, as opposed to a switch intended for frequent user interaction (e.g., a wall dimmer).
- Technical Questions: For the '251 Patent, a central technical question may be whether the accused "driver" performs the claimed function of outputting a "relatively higher frequency" than its input. Analysis would be required to determine if the accused circuitry is a simple rectifier or a more complex frequency-converting power supply as contemplated by the patent.
V. Key Claim Terms for Construction
The Term: "an LED driver...provides an output of a second voltage and a second frequency...wherein the second frequency of the output is a relatively higher frequency than the first frequency of the input" (’251 Patent, Claim 11)
- Context and Importance: This term is critical because the infringement theory for CCT-selectable products under the '251 patent relies on the accused on-board circuitry meeting this functional definition of an "LED driver." Practitioners may focus on this term because the accused products appear to use simple Driver-on-Board circuits, and the dispute may turn on whether these circuits perform the claimed frequency conversion.
- Intrinsic Evidence for Interpretation:
- Evidence for a Broader Interpretation: The specification states that the driver provides a "relatively fixed voltage and relatively fixed frequency AC output even with changes to the load" and can be a "mains power source, a high frequency LED circuit driver or other LED circuit driver." ('251 Patent, col. 5:48-65).
- Evidence for a Narrower Interpretation: The specification repeatedly discusses "higher frequency inverter drivers" as a preferred embodiment, which "are preferred enabling smaller package designs of LED circuits." ('251 Patent, col. 5:14-19). A defendant may argue this context limits the claim to drivers that perform active frequency up-conversion, not simple rectification.
The Term: "a switch configured to enable user selection" (’783 Patent, Claim 8)
- Context and Importance: The infringement allegation for CCT products under the '783 patent hinges on the physical toggle switch integrated into the accused light fixtures. Practitioners may focus on this term because its construction will determine whether a switch set once at installation falls within the scope of "user selection," which could also be interpreted to mean ongoing, dynamic control by the end-user.
- Intrinsic Evidence for Interpretation:
- Evidence for a Broader Interpretation: The patent does not explicitly limit the type or location of the switch. An instructional diagram in the complaint, allegedly from the product, shows a "toggle switch on the inside of the fixture body" for making a color selection, which directly aligns with the accused product's design. (Compl. p. 36).
- Evidence for a Narrower Interpretation: The specification discusses a "dimmer switch" that can be "coupled to the LED driver" to adjust voltage or frequency. ('783 Patent, col. 13:3-9). A defendant may argue that "user selection" in this context implies a more readily accessible control, like a wall switch, rather than a switch inside the fixture housing.
VI. Other Allegations
Indirect Infringement
- The complaint alleges inducement of infringement by alleging that Defendant sells the accused products with "accompanying instructions for use" that instruct end-users on how to operate the infringing features, such as the color-selection switch. (Compl. ¶¶69, 82, 95). The complaint also alleges inducement of third-party vendors to manufacture the products according to Home Depot's specifications. (Compl. ¶¶71, 84, 97).
Willful Infringement
- The complaint alleges willful infringement based on Defendant's alleged knowledge of the patents-in-suit. It is alleged that Defendant was first made aware of Plaintiff's patent portfolio in January 2018 and received specific notice of infringement for each patent as it issued, but continued to expand its sales of the accused products. (Compl. ¶¶31-38, 76, 89, 102).
VII. Analyst’s Conclusion: Key Questions for the Case
- A threshold issue for the litigation is the impact of post-filing invalidations: a significant number of the asserted claims, including all asserted claims from six of the nine patents, were cancelled in subsequent IPR and PGR proceedings. The court must first address the legal status of a complaint where the majority of the underlying patent claims are no longer valid.
- For any surviving claims, a central technical question will be one of functional operation: do the accused products' relatively simple integrated driver circuits perform the specific functions required by the claims, such as the frequency up-conversion recited in the '251 patent, or is there a fundamental mismatch in how the technology operates?
- A key claim construction question will be one of definitional scope: can the term "switch configured to enable user selection," as used in the '783 patent, be construed to cover a physical switch on the body of a lighting fixture that is typically set once during installation, or does the patent's context require a control more accessible for dynamic user interaction?