DCT
1:23-cv-00769
Signify North America Corp v. Current Lighting Solutions LLC
I. Executive Summary and Procedural Information
- Parties & Counsel:
- Plaintiff: Signify North America Corporation (Delaware) & Signify Holding B.V. (Netherlands)
- Defendant: Current Lighting Solutions, LLC (Delaware)
- Plaintiff’s Counsel: Morris, Nichols, Arsht & Tunnell LLP; Alston & Bird LLP
- Case Identification: 1:23-cv-00769, D. Del., 07/14/2023
- Venue Allegations: Venue is alleged to be proper based on Defendant being a Delaware limited liability company, conducting business through distributors in the district, committing alleged acts of infringement in the district, and having previously been subject to proper venue in the district in a separate case.
- Core Dispute: Plaintiff alleges that Defendant’s LED luminaires and downlights infringe three patents related to LED driver circuitry, the mechanical design of downlight fixtures, and surge protection technology.
- Technical Context: The dispute centers on foundational technologies in the LED lighting market, which has largely superseded older lighting solutions due to significant advantages in energy efficiency and operational lifespan.
- Key Procedural History: The complaint alleges that Defendant had pre-suit notice of its potential infringement of two patents as early as June 2018 and of a third patent as early as August 2022. It is also alleged that Defendant filed, but did not serve, a declaratory judgment action regarding two of the patents-in-suit in June 2023, one month prior to the filing of this complaint.
Case Timeline
| Date | Event |
|---|---|
| 2004-11-29 | Earliest Priority Date for '577 Patent |
| 2009-01-13 | Priority Date for '328 Patent |
| 2011-11-22 | '577 Patent Issued |
| 2011-12-06 | '328 Patent Issued |
| 2013-07-03 | Priority Date for '268 Patent |
| 2015-08-25 | '268 Patent Issued |
| 2018-06-22 | Alleged pre-suit notice of '577 and '328 Patent infringement |
| 2022-08-20 | Alleged pre-suit notice of '268 Patent infringement |
| 2023-06-22 | Defendant allegedly filed declaratory judgment action |
| 2023-07-14 | Complaint Filed |
II. Technology and Patent(s)-in-Suit Analysis
U.S. Patent No. 8,063,577 - "Method and a Driver Circuit for LED Operation" (Issued Nov. 22, 2011)
The Invention Explained
- Problem Addressed: The patent’s background section describes prior art electronic current sources for LEDs as being suboptimal in terms of efficiency, cost, size, and reliability, noting that “hard-switched” converters result in low efficiency and require large electromagnetic interference (EMI) filters (ʼ577 Patent, col. 1:15-41).
- The Patented Solution: The invention is a driver circuit that aims to improve efficiency by using a resonant topology. A resonant capacitor is placed in series with the primary winding of a transformer, which allows for “zero voltage switching” of the power-generating components, reducing switching losses (ʼ577 Patent, col. 2:56-59; Fig. 1). The circuit transforms and rectifies an alternating current to produce a “substantially constant” direct current to power the LEDs, using an inductor in the output stage to buffer the current (ʼ577 Patent, Abstract; col. 5:58-64).
- Technical Importance: This design sought to create more efficient and compact power supplies (drivers) for LED lighting, a critical step in making LED technology a viable replacement for less efficient, conventional lighting systems (ʼ577 Patent, col. 1:5-14).
Key Claims at a Glance
- The complaint asserts at least independent claim 1 (Compl. ¶32).
- The essential elements of independent claim 1 include:
- A driver circuit comprising a set of input terminals, a resonant capacitor, and a transformer with its primary winding and the capacitor coupled in series to the input terminals.
- A “rectifier means” coupled to the transformer's secondary winding.
- An output circuit coupled to the rectifier that includes “buffer circuitry” and output terminals for the LED.
- The buffer circuitry comprises an inductor connected in series with the output terminals, with the inductor's value being “selected to provide a substantially constant current through the LED.”
- The complaint reserves the right to assert additional claims (Compl. ¶30).
U.S. Patent No. 8,070,328 - "LED Downlight" (Issued Dec. 6, 2011)
The Invention Explained
- Problem Addressed: The patent describes the need for a downlight fixture that leverages the efficiency and long life of LEDs while also providing good optical control, specifically a “clear cutoff with minimal glare,” which is a key aesthetic and functional requirement for architectural lighting (ʼ328 Patent, col. 1:50-53).
- The Patented Solution: The invention is a specific mechanical and optical assembly for an LED downlight. It features a “multi-piece reflector assembly” composed of a first, upper reflector and a second, lower reflector that together define a light exit passageway ('328 Patent, Abstract). Critically, a “diffuser” is positioned at the junction between these two reflectors, which smooths the light output and reduces glare from the individual LED sources ('328 Patent, col. 2:1-4; Fig. 6). The LED array is mounted above the assembly on a heatsink to manage thermal output ('328 Patent, col. 1:57-65).
- Technical Importance: The claimed structure provides a way to harness the benefits of powerful LEDs in downlighting applications without the harshness or “hot spots” that can result from using point-like light sources, thus improving visual comfort (ʼ328 Patent, col. 7:1-8).
Key Claims at a Glance
- The complaint asserts at least independent claim 1 (Compl. ¶52).
- The essential elements of independent claim 1 include:
- An LED downlight fixture with an array of LEDs in thermal connectivity with a heatsink.
- A “multi-piece reflector assembly” including a first reflector and a second reflector, each with specific apertures.
- The second reflector is positioned relative to the first reflector to define a “light exit passageway.”
- A “diffuser positioned proximal to and extending across” the second aperture of the first reflector and the first aperture of the second reflector.
- The complaint reserves the right to assert additional claims (Compl. ¶53).
U.S. Patent No. 9,119,268 - "Driver with Isolation and Surge Signal Protection" (Issued August 25, 2015)
- Patent Identification: U.S. Patent No. 9,119,268, "Driver with Isolation and Surge Signal Protection," issued August 25, 2015 (Compl. ¶15).
- Technology Synopsis: This patent describes a circuit for protecting LEDs and their drivers from common mode electrical surges. The invention uses an “isolation circuit” (e.g., a transformer) to separate the input and output sides, combined with a “guiding circuit” (e.g., capacitors) connected to a reference potential. This configuration is designed to divert potentially damaging surge energy away from the sensitive light circuit components ('268 Patent, Abstract; col. 1:44-54).
- Asserted Claims: The complaint asserts at least independent claim 1 (Compl. ¶68, ¶70).
- Accused Features: The “UltraMax™ Programmable LED Driver” within the Albeo LED Luminaire is alleged to contain the claimed isolation and surge protection circuitry (Compl. ¶21, ¶71).
III. The Accused Instrumentality
Product Identification
The complaint identifies three exemplary product families: the Lumination LED Recessed Luminaire, the LRXBR 6inch Downlight, and the Albeo LED Luminaire (Modular High & Low Bay) (Compl. ¶19-21).
Functionality and Market Context
The accused instrumentalities are commercial-grade LED lighting fixtures sold by Defendant Current Lighting Solutions, LLC for various indoor lighting applications (Compl. ¶8, ¶17). The complaint alleges that the Lumination and Albeo products contain an “UltraMax™ Programmable LED Driver,” which is the component accused of infringing the ’577 and ’268 patents (Compl. ¶35, ¶71). The LRXBR 6inch Downlight is a recessed fixture whose mechanical and optical structure is accused of infringing the ’328 Patent (Compl. ¶55-58). An image of the accused Lumination luminaire shows a rectangular troffer-style light fixture (Compl. ¶19). An image of the accused Albeo luminaire shows a modular high bay fixture (Compl. ¶21).
IV. Analysis of Infringement Allegations
’577 Patent Infringement Allegations
| Claim Element (from Independent Claim 1) | Alleged Infringing Functionality | Complaint Citation | Patent Citation |
|---|---|---|---|
| A driver circuit... configured to control a current to be supplied to the LED | The accused Lumination luminaire includes an “UltraMax™ Programmable LED Driver” configured to operate LEDs by controlling the supplied current. | ¶35 | col. 5:45-48 |
| a set of input terminals for receiving a supply voltage | The accused driver includes a set of input terminals for receiving a supply voltage. | ¶36 | col. 5:48-54 |
| a resonant capacitor | The accused driver includes a resonant capacitor (e.g., C101). | ¶37 | col. 5:21-22 |
| a transformer, a primary winding of the transformer and the resonant capacitor being coupled in series to the set of input terminals | The accused driver includes a transformer (e.g., T103), and its primary winding is coupled in series with the resonant capacitor to the input terminals. | ¶38 | col. 5:21-24 |
| a rectifier means coupled to the secondary winding of the transformer for rectifying an alternating load voltage... | The accused driver includes a rectifier means (e.g., diodes D198 and D199) coupled to the secondary winding of the transformer. | ¶39 | col. 5:35-37 |
| an output circuit coupled to the rectifier means... comprising a buffer circuitry and a set of output terminals... | The accused driver includes an output circuit (e.g., inductor T101 and output terminals J4 and J5) coupled to the rectifier, which comprises buffer circuitry and output terminals. | ¶40 | col. 5:38-40 |
| wherein the buffer circuitry comprises an inductor connected in series with the set of output terminals, and the value of the inductor is selected to provide a substantially constant current through the LED | The accused driver’s buffer circuitry includes an inductor (e.g., T101) connected in series with the output terminals, and its value is allegedly selected to provide a substantially constant current through the LED. | ¶41 | col. 5:60-64 |
- Identified Points of Contention:
- Scope Questions: The claim requires the inductor's value to be “selected to provide a substantially constant current.” The dispute may center on the definition of “substantially constant.” A key question for the court will be what degree of current ripple or fluctuation falls within the scope of this term.
- Technical Questions: What evidence demonstrates that the inductor was specifically “selected” for this purpose, as opposed to its value being a consequence of other design constraints? The infringement analysis will depend on evidence of the accused driver's actual performance and design intent.
’328 Patent Infringement Allegations
The complaint provides several annotated photographs of the accused LRXBR 6inch Downlight to support its allegations. For example, a labeled teardown photograph of the accused product identifies the alleged “First reflector,” “Second reflector,” and their respective apertures (Compl. ¶57). Another image isolates and identifies the “Diffuser” component (Compl. ¶58).
| Claim Element (from Independent Claim 1) | Alleged Infringing Functionality | Complaint Citation | Patent Citation |
|---|---|---|---|
| an array of LEDs in thermal connectivity with a heatsink, said array of LEDs positioned adjacent a first aperture of a multi-piece reflector assembly | The accused LRXBR Downlight allegedly comprises an array of LEDs on a board in thermal contact with a heatsink, with the LEDs positioned adjacent to the first aperture of a reflector assembly. An annotated image shows the alleged 'Heat sink' and 'Array of LEDs' (Compl. ¶56). | ¶56 | col. 1:57-65 |
| said multi-piece reflector assembly including: a first reflector having said first aperture... and an opposed larger second aperture... | The accused product's reflector assembly allegedly includes a first reflector with a first aperture in its upper portion and a larger second aperture in its lower portion. | ¶57 | col. 2:60-65 |
| a second reflector having a first aperture positioned adjacent said second aperture of said first reflector and a second aperture opposite... defining a light exit passageway | The accused product allegedly includes a second reflector with a first aperture positioned next to the second aperture of the first reflector, defining a light exit passageway. | ¶57 | col. 2:60-65 |
| a diffuser positioned proximal to and extending across said second aperture of said first reflector and said first aperture of said second reflector | The accused LRXBR Downlight allegedly comprises a diffuser positioned to extend across the boundary between the first and second reflectors (i.e., across the second aperture of the first reflector and the first aperture of the second reflector). | ¶58 | col. 2:1-4 |
- Identified Points of Contention:
- Scope Questions: The infringement case for the ’328 Patent may turn on the construction of the phrase “positioned proximal to and extending across.” Does this require the diffuser to be physically captured between the two reflector components, or can it be met if the diffuser is simply near their junction?
- Technical Questions: Does the physical arrangement of the accused downlight's components match the specific spatial relationships required by the claim? The defendant could argue that its diffuser is located entirely within the second reflector or is otherwise positioned in a way that does not “extend across” the apertures of both reflectors as claimed.
V. Key Claim Terms for Construction
’577 Patent: "substantially constant current"
- Context and Importance: This term, appearing in the final limitation of asserted claim 1, is a qualitative descriptor of the circuit’s performance. Its interpretation is critical because whether the accused driver's output meets this standard will be a central point of the infringement analysis.
- Intrinsic Evidence for Interpretation:
- Evidence for a Broader Interpretation: The patent specification uses the phrase without providing a specific numerical range for acceptable current ripple, which may support an argument for applying its plain and ordinary meaning, allowing for some degree of fluctuation (ʼ577 Patent, col. 5:25-29).
- Evidence for a Narrower Interpretation: The specification consistently links this outcome to the function of the “buffer element” or “output choke,” suggesting the term should be understood in the context of a circuit whose inductor is specifically chosen for current-smoothing, not a circuit that incidentally has a relatively stable output (ʼ577 Patent, Abstract; col. 5:58-64).
’328 Patent: "a diffuser positioned proximal to and extending across said second aperture of said first reflector and said first aperture of said second reflector"
- Context and Importance: This limitation defines the precise location of the diffuser relative to the two-part reflector, which is the core structural innovation claimed by the patent. Infringement hinges on whether the accused product's physical assembly meets this specific geometric configuration.
- Intrinsic Evidence for Interpretation:
- Evidence for a Broader Interpretation: The summary of the invention describes an embodiment where the diffuser is “captured between the first reflector and the second reflector,” which could imply that this is one specific, but not the only, way to satisfy the “proximal to and extending across” requirement (ʼ328 Patent, col. 2:28-30).
- Evidence for a Narrower Interpretation: The embodiment depicted in Figure 6 and the corresponding description show the diffuser (74) seated in a mounting ring (70) that places it directly at the physical interface between the upper (52) and lower (54) reflectors. This could support a narrower construction requiring the diffuser to be located at, and bridge, the literal junction of the two components ('328 Patent, Fig. 6; col. 6:53-61).
VI. Other Allegations
- Indirect Infringement: For all three patents-in-suit, the complaint alleges active inducement based on Defendant's sale of products with infringing features and the provision of instructions and marketing materials that encourage infringing use (Compl. ¶45, ¶61, ¶80). It also alleges contributory infringement, arguing that the accused components (e.g., LED drivers) are not staple articles of commerce and are especially made or adapted for use in an infringing manner (Compl. ¶46, ¶62, ¶81).
- Willful Infringement: The complaint alleges that Defendant had pre-suit knowledge of all three patents. Notice for the ’577 and ’328 patents is alleged as of June 22, 2018, and for the ’268 Patent as of August 20, 2022 (Compl. ¶43, ¶60, ¶78). The complaint further alleges that Defendant's own unserved declaratory judgment action demonstrates its awareness of the patents (Compl. ¶44, ¶79). The willfulness claim is based on Defendant’s alleged continued infringement after receiving notice (Compl. ¶24, ¶47, ¶63, ¶82).
VII. Analyst’s Conclusion: Key Questions for the Case
- A central issue for the ’328 Patent will be one of structural definition: can the claim term “positioned proximal to and extending across” the apertures of two distinct reflectors be construed to read on the accused downlight's assembly, or is there a definitive spatial mismatch between the claim language and the product’s physical construction?
- For the ’577 Patent, a key evidentiary question will be one of functional performance: does the accused driver circuit’s inductor, as a matter of technical fact, produce a “substantially constant current” under typical operating conditions, and was it “selected” for this purpose as required by the claim?
- Given the allegations of pre-suit notice dating back several years, a significant question underlying the entire case will be willfulness: if infringement is found, did Defendant’s continued sale of the accused products after receiving notice from Plaintiff constitute objectively reckless behavior sufficient to warrant enhanced damages under 35 U.S.C. § 284?