Noxgear LLC v. Dexscout

I. Executive Summary and Procedural Information

• Parties & Counsel:
  • Plaintiff: Noxgear, LLC (Ohio)
  • Defendant: DEXSCOUT aka SHENZHENSHI GUXIANG ZHINENG SHEBEI YOUXIAN ZEREN GONGSI (China)
  • Plaintiff's Counsel: Workman Nydegger
• Case Identification: 2:26-cv-00159, D. Utah, 03/05/2026
• Venue Allegations: Venue is alleged to be proper as Defendant is a foreign corporation subject to personal jurisdiction in the district and transacts business in the district through Amazon.com, which is alleged to operate a principal place of business there.
• Core Dispute: Plaintiff alleges that Defendant's DexScout portable audio speaker products infringe a patent related to the mechanical and electronic design of a wearable audio speaker system.
• Technical Context: The technology at issue concerns small, lightweight, wearable Bluetooth speakers designed for active users, a market segment where portability, battery life, and audio performance are key competitive factors.
• Key Procedural History: The asserted patent is a divisional from a family of applications tracing priority to a 2019 provisional application. The complaint does not mention any prior litigation or administrative proceedings involving the patent.

Case Timeline

Date	Event
2019-10-18	Priority Date for U.S. Patent No. 12,520,081
2020-06-28	FCC Registration Date for entity allegedly related to Defendant
2026-01-06	U.S. Patent No. 12,520,081 Issued
2026-03-05	Complaint Filing Date

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

U.S. Patent No. 12,520,081 - "Portable audio speaker system"

• Patent Identification: U.S. Patent No. 12,520,081, titled "Portable audio speaker system," issued January 6, 2026 (the "''081 Patent").

The Invention Explained

• Problem Addressed: The patent describes the limitations of conventional wearable speakers, noting that standard mechanical clips are restricted to edges of clothing and that magnetic clips are unsuitable for thicker materials like belts or straps ʼ081 Patent, col. 2:5-25 Additionally, it identifies an issue where speakers facing directly away from a user's body result in attenuated high-frequency sounds (treble) and require more power to achieve a desired volume ʼ081 Patent, col. 4:5-18
• The Patented Solution: The invention is a portable audio speaker system featuring specific electronic architecture to solve the power and audio quality problem. The core electronic solution described is an audio amplifier that incorporates a boost converter. This converter is configured to take the low voltage from a single-cell lithium battery and increase it to a more powerful "about 5 to 6 volts" level, which then drives the speaker element using a pulse-width modulation (PWM) signal ʼ081 Patent, claim 15 This design aims to produce a higher sound pressure level (SPL) from a small, power-efficient device ʼ081 Patent, col. 15:39-44
• Technical Importance: The patented approach addresses the technical challenge of delivering loud, high-quality audio from a very small, lightweight, battery-powered device, which is a critical design constraint for electronics intended to be worn during physical activity ʼ081 Patent, col. 1:59-66

Key Claims at a Glance

• The complaint asserts independent claim 15 Compl. ¶22
• The essential elements of claim 15 include:
  • A speaker assembly with a housing, a speaker element, an audio amplifier, and an internal power supply with a single-cell lithium battery.
  • A clip member and a spring element that form a "clipping device" for attaching to the edge of an item.
  • A functional requirement that the audio amplifier uses pulse-width modulation (PWM).
  • A structural and functional requirement that the audio amplifier "comprises a boost converter configured to raise the single-cell lithium battery to a voltage of about 5 to 6 volts."
• The complaint's prayer for relief seeks judgment on "one or more claims," which preserves the right to assert other claims, including dependent claims Compl. p. 23

III. The Accused Instrumentality

Product Identification

The accused products are portable speakers sold by Defendant under the "DexScout" brand on Amazon.com, identified by ASINs including B0D6YMRNRH Compl. ¶2 Compl. ¶15 Compl. ¶24

Functionality and Market Context

The complaint alleges the Accused Product is a wearable Bluetooth speaker that functions as a direct competitor to Plaintiff's own "39g" speaker Compl. ¶14 Compl. ¶15 The complaint provides extensive technical analysis of the Accused Product, including teardown photographs and identification of specific internal components. It alleges the Accused Product contains a housing, an internal speaker, a clip with a spring, and a single-cell lithium battery Compl. ¶¶24-30 Crucially, the complaint alleges the product uses a specific audio amplifier integrated circuit, the "PAM8945," which allegedly performs the functions required by the asserted patent claim Compl. ¶26

IV. Analysis of Infringement Allegations

The complaint's infringement theory is presented through a detailed, element-by-element breakdown, supported by photographs and excerpts from a component datasheet.

'081 Patent Infringement Allegations

Claim Element (from Independent Claim 15)	Alleged Infringing Functionality	Complaint Citation	Patent Citation
a portable audio speaker system, comprising: at least one speaker assembly including a housing; a speaker element disposed within the housing;	The Accused Product is a portable speaker with an external housing containing an internal speaker element. A teardown photograph shows the speaker element inside the housing.	¶24	col. 7:16-20
an audio amplifier coupled to the speaker element;	The Accused Product contains an integrated circuit ("IC") marked "P8945 CUA4Y," which is identified as the PAM8945 audio amplifier. Photos show this IC on the circuit board connected to the speaker.	¶¶25-27	col. 15:10-14
an internal power supply comprising a single-cell lithium battery;	A photograph of the Accused Product's internals shows a single 3.7V lithium battery.	¶28	col. 15:4-6
a clip member coupled to the housing...and a spring element coupling the clip member to the housing;	Photographs show a clip mechanism on the rear of the Accused Product, with an internal photograph displaying the torsion spring that actuates it.	¶¶29-30	col. 8:55-58
wherein the clipping device allows the housing to be coupled to, and decoupled from, an edge of an item;	A photograph depicts the Accused Product's clip being attached to the edge of a piece of fabric.	¶31	col. 8:45-48
wherein the audio amplifier provides a switched voltage audio signal to the speaker element via pulse-width modulation (PWM);	The complaint presents a functional block diagram from the alleged datasheet for the PAM8945 IC, which explicitly shows a "PWM Modulator" block in the signal path.	¶32	col. 15:10-12
wherein the audio amplifier comprises a boost converter configured to raise the single-cell lithium battery to a voltage of about 5 to 6 volts for driving the speaker element via the PWM.	The complaint cites the same PAM8945 datasheet, which includes a "Boost Convertor" block. An "Electrical Characteristics" table from the datasheet is also provided, listing a "Peak Output Voltage" with a typical value of 5.75 V.	¶33	col. 15:63-65

• Identified Points of Contention:
  • Evidentiary Question: The infringement case hinges on the allegation that the Accused Products contain the PAM8945 integrated circuit or an equivalent with the same functionality. A central question for the court will be an evidentiary one: what proof will be offered to establish that all units of the Accused Product sold by the Defendant contain this specific component and that the provided datasheet accurately describes its function?
  • Scope Question: A potential, though perhaps secondary, point of contention could arise over the term "about 5 to 6 volts." While the accused device's alleged 5.75V peak output falls within this range, parties in patent litigation often dispute the scope of such modifiers. The analysis will question what range the term "about" encompasses in the context of the patent's specification and prosecution history.

V. Key Claim Terms for Construction

• The Term: "boost converter"
• Context and Importance: This term is central to the patent's asserted novelty and the final, most specific limitation of claim 15. The infringement allegation is heavily dependent on the Accused Product's amplifier containing a component that meets this definition. Practitioners may focus on this term because the plaintiff has tied its infringement read directly to a specific third-party component alleged to be a boost converter.
• Intrinsic Evidence for Interpretation:
  • Evidence for a Broader Interpretation: The patent specification describes the boost converter in functional terms as part of the amplifier, configured to "raise the single-cell lithium battery to a voltage of about 5 to 6 volts" ʼ081 Patent, claim 15 The block diagram in Figure 21 is generic ʼ081 Patent, Fig. 21 Plaintiff may argue this supports a broad, functional definition consistent with the term's plain and ordinary meaning in electrical engineering.
  • Evidence for a Narrower Interpretation: A defendant could scrutinize the specification for any language that might limit the "boost converter" to a specific topology or operational characteristic not present in the accused device. However, the patent appears to describe the element at a high functional level, which may make finding such limitations challenging.
• The Term: "about 5 to 6 volts"
• Context and Importance: This phrase defines the required output of the "boost converter." The complaint alleges the accused device has a typical peak output of 5.75V, making the interpretation of "about" relevant to the infringement analysis.
• Intrinsic Evidence for Interpretation:
  • Evidence for a Broader Interpretation: The use of "about" itself suggests the patentee did not intend to be limited to the precise numerical range. A party arguing for a broader interpretation would state that 5.75V is definitionally "about 5 to 6 volts."
  • Evidence for a Narrower Interpretation: A party seeking a narrower scope would analyze the specification to see if the 5-to-6-volt range is described as a critical threshold, potentially arguing that "about" should be construed narrowly. Given the facts alleged, where the accused value is squarely within the range, this may be a difficult position to sustain.

VI. Other Allegations

• Indirect Infringement: The complaint makes a placeholder allegation of indirect infringement but provides no specific factual basis for either induced or contributory infringement, such as evidence of instructions or components with no substantial non-infringing use Compl. ¶35
• Willful Infringement: Willfulness is alleged based on Defendant's purported knowledge of the patent, at least as of the filing of the complaint Compl. ¶35 Compl. ¶37 The complaint uses standard language alleging the infringement was "willfully blind," but does not plead specific facts demonstrating pre-suit knowledge.

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

1. A question of Evidentiary Proof: The case appears to turn on a core factual question: does the Defendant's Accused Product consistently incorporate the PAM8945 integrated circuit or an equivalent that performs the functions of a boost converter raising voltage to ~5.75V via PWM, as the complaint's detailed teardown and component analysis alleges?
2. A question of Technical Equivalence: Beyond confirming the presence of the specific IC, the court may need to resolve whether the operation of the PAM8945 circuit is technically equivalent to the "audio amplifier compris[ing] a boost converter" as claimed, which will involve a detailed comparison of the circuit's function against the language of the patent claim.
3. A question of Definitional Scope: While secondary to the evidentiary question, the case will also involve the construction of "about 5 to 6 volts." The key question here is whether the defendant can create a non-infringement argument by demonstrating that the accused device operates outside a narrowly construed definition of this range, despite the complaint's evidence showing a typical performance of 5.75V.