Shenzhen Shokz Co Ltd v. Shenzhen Wenming Technology Co Ltd

I. Executive Summary and Procedural Information

• Parties & Counsel:
  • Plaintiff: Shenzhen Shokz Co., Ltd. (People's Republic of China)
  • Defendant: Shenzhen Wenming Technology Co., Ltd., et al. (People's Republic of China and United States)
  • Plaintiff’s Counsel: Perkins Coie LLP
• Case Identification: 1:24-cv-06717, N.D. Ill., 07/31/2024
• Venue Allegations: Plaintiff alleges venue is proper because Defendants import, sell, and distribute the accused products throughout the United States, including in the Northern District of Illinois, through various e-commerce storefronts. One defendant, Mrneio LLC, is alleged to be an Illinois company with a principal place of business in the district.
• Core Dispute: Plaintiff alleges that Defendants’ Mojawa-branded bone conduction headphones infringe two U.S. patents related to the structural and acoustic design of waterproof loudspeaker apparatuses.
• Technical Context: The technology concerns the design of bone conduction headphones, which transmit sound via vibration through the user's skull, with a focus on improving water resistance and reducing sound leakage.
• Key Procedural History: The complaint does not allege any prior litigation, licensing history between the parties, or post-grant proceedings involving the patents-in-suit.

Case Timeline

Date	Event
2019-01-05	Earliest Priority Date for ’084 and ’582 Patents
2021-12-07	U.S. Patent No. 11,197,084 Issues
2022-04-19	U.S. Patent No. 11,310,582 Issues
2024-07-31	Complaint Filed

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

U.S. Patent No. 11,197,084 - "Loudspeaker apparatus," issued December 7, 2021

The Invention Explained

• Problem Addressed: The patent identifies a need for earphones that can be used in "special scenes (e.g., swimming, rainy days, etc.)" and that possess a waterproof function while also being easy to produce and assemble (’084 Patent, col. 1:26-33).
• The Patented Solution: The invention is a loudspeaker apparatus, such as a bone conduction headphone, featuring a specific structural arrangement to enhance waterproofing and sound quality. It comprises an ear hook surrounded by an elastic, waterproof "protective sleeve." A "core housing" containing the earphone's vibration-producing core is fixed to one end of the ear hook and "elastically abutted" against the sleeve to create a seal (’084 Patent, Abstract). The patent also discloses that the "driving force" generated by the earphone core to create vibration is "not parallel to a normal line of the housing panel," an orientation intended to improve sound quality (’084 Patent, col. 1:48-52; Fig. 12).
• Technical Importance: The design aims to solve two key challenges in sports headphones: achieving robust water resistance through a specific sealing structure and improving the user's acoustic experience by controlling the angle of the transducer's driving force (’084 Patent, col. 1:30-33, col. 22:35-44).

Key Claims at a Glance

• The complaint asserts infringement of at least independent claim 1 (Compl. ¶24).
• The essential elements of Claim 1 are:
  • An ear hook with a first and second plug end, surrounded by a protective sleeve made of an elastic waterproof material.
  • A core housing that accommodates an earphone core, is fixed to the first plug end, and is "elastically abutted" against the protective sleeve.
  • A circuit housing for a battery or control circuit, fixed to the second plug end.
  • The battery/circuit drives the earphone core to vibrate, generating a driving force to vibrate a housing panel, where the "driving force being not parallel to a normal line of the housing panel."
• The complaint reserves the right to assert infringement of other claims of the ’084 Patent (Compl. ¶23).

U.S. Patent No. 11,310,582 - "Loudspeaker apparatus," issued April 19, 2022

The Invention Explained

• Problem Addressed: In addition to waterproofing, this patent addresses the problem of "leaked sound," where vibrations from an open-ear headphone transmit sound into the surrounding environment rather than solely to the user, potentially compromising privacy (’582 Patent, col. 3:5-10, col. 35:15-19).
• The Patented Solution: The invention discloses a loudspeaker with a core housing that has a "housing panel" facing the user and an opposing "housing back panel." To reduce sound leakage, the design controls the phase relationship between the vibrations of these two panels. The patent claims that when the vibration frequency is between 2000 Hz and 3000 Hz, the absolute difference between the vibration phase of the housing panel and the housing back panel is less than 60 degrees. This specific phase relationship is designed to cause the sound waves leaking from the front and back to interfere with and cancel each other out (’582 Patent, Abstract).
• Technical Importance: The claimed phase-cancellation technique provides a technical solution to sound leakage, a significant drawback of open-ear and bone conduction headphones, by manipulating the acoustic properties of the device's housing itself (’582 Patent, col. 3:5-10).

Key Claims at a Glance

• The complaint asserts infringement of at least independent claim 1 (Compl. ¶47).
• The essential elements of Claim 1 are:
  • An ear hook with a first and second plug end, surrounded by a protective sleeve made of an elastic waterproof material.
  • A core housing that accommodates an earphone core, is fixed to the first plug end, and is "elastically abutted" against the protective sleeve.
  • The core housing includes a "housing panel" facing the human body and an opposite "housing back panel."
  • The vibration of the housing panel has a first phase, and the vibration of the housing back panel has a second phase.
  • When vibration frequencies are within a range of 2000 Hz to 3000 Hz, the "absolute value of a difference between the first phase and the second phase is less than 60 degrees."
  • A circuit housing for a battery or control circuit, fixed to the second plug end.
• The complaint reserves the right to assert infringement of other claims of the ’582 Patent (Compl. ¶46).

III. The Accused Instrumentality

Product Identification

• The complaint identifies the Mojawa-branded "Run SE (Mojo 1)," "Run Air (Mojo 2)," and "Run Plus" bone conduction headphones as the accused instrumentalities (Compl. ¶¶24, 47).

Functionality and Market Context

• The accused products are wireless, Bluetooth-enabled bone conduction headphones marketed for sports and general consumer use (Compl. ¶¶9-10). The complaint notes they are promoted with an "IP67 Waterproof" rating and are sold on e-commerce platforms such as Amazon.com, eBay.com, and mojawa.com (Compl. ¶¶12, 28, 36). The complaint includes detailed allegations based on product teardowns and marketing materials to describe the internal components and their arrangement (Compl. ¶¶26-31, 49-57). For example, a teardown photograph shows the core housing fixed to the first plug end and elastically abutted against the protective sleeve (Compl. ¶29).

IV. Analysis of Infringement Allegations

11,197,084 Infringement Allegations

Claim Element (from Independent Claim 1)	Alleged Infringing Functionality	Complaint Citation	Patent Citation
an ear hook including a first plug end and a second plug end, the ear hook being surrounded by a protective sleeve, the protective sleeve being made of an elastic waterproof material	The accused Mojo 1 and Mojo 2 products are alleged to have an ear hook with two plug ends, covered by a protective sleeve made of an elastic, waterproof material, as evidenced by product photos and an "IP67 Waterproof" rating.	¶¶26-28, 34-36	col. 9:1-11
a core housing for accommodating an earphone core, the core housing being fixed to the first plug end and elastically abutted against the protective sleeve	Teardown photos allegedly show a "core housing" containing an "earphone core" that is fixed to the "first plug end" and "elastically abutted" against the sleeve to achieve a seal.	¶¶29, 37	col. 1:40-44
a circuit housing for accommodating a control circuit or a battery, the circuit housing being fixed to the second plug end...the control circuit or the battery driving the earphone core to vibrate	Teardown photos allegedly show a "circuit housing" fixed to the "second plug end" that contains a battery, which is alleged to be the power source that drives the earphone core.	¶¶30-31, 38-39	col. 1:45-48
the vibration of the earphone core generating a driving force to drive a housing panel of the core housing to vibrate, the driving force being not parallel to a normal line of the housing panel	The complaint provides a diagram, purportedly showing the operation of the accused products, that depicts the "driving force" as being non-parallel to the "normal line" of the housing panel.	¶¶32-33, 40-41	col. 1:48-52

• Identified Points of Contention:
  • Technical Questions: A primary technical question concerns the final limitation regarding the non-parallel driving force. The complaint provides a diagram to support this allegation (Compl. ¶¶33, 41). The accuracy of this diagram and whether the accused product's transducer operates in the claimed manner will be a central point of dispute, likely requiring expert analysis of the device's internal mechanics and vibration patterns.
  • Scope Questions: The construction of "elastically abutted" may become a focus. The complaint alleges this feature but provides limited direct evidence of the abutment's elastic properties. The parties may dispute whether the simple contact shown in teardown photos (Compl. ¶29) meets the claim's requirement for an elastic, sealing abutment.

11,310,582 Infringement Allegations

Claim Element (from Independent Claim 1)	Alleged Infringing Functionality	Complaint Citation	Patent Citation
...core housing including a housing panel facing human body and a housing back panel opposite to the housing panel...	The complaint provides photographs of the accused Mojo 1 product identifying a "housing panel" and an opposing "housing back panel." A product marketing photo shows the housing panel facing the user's body.	¶¶53, 62, 71	col. 17:15-18
...the vibration of the housing panel having a first phase, the vibration of the housing back panel having a second phase...	The complaint alleges that the vibration of the earphone core causes both the housing panel and the housing back panel to vibrate, and that these vibrations have distinct phases.	¶¶54, 63, 72	col. 17:19-21
when the vibration frequencies...is within a range of 2000 Hz to 3000 Hz, an absolute value of a difference between the first phase and the second phase is less than 60 degrees	The complaint presents graphs, allegedly derived from testing the Mojo 1 and Mojo 2 products, showing the measured phase difference between the panels is below 60 degrees across the 2000-3000 Hz frequency range.	¶¶55, 64, 73	col. 17:21-26

• Identified Points of Contention:
  • Technical Questions: The infringement allegation for the ’582 patent hinges entirely on the factual accuracy of the phase-difference measurements presented in the complaint's graphs (Compl. ¶¶55, 64, 73). A significant point of contention will be the validity of the plaintiff's testing methodology and data. The court will likely need to resolve conflicting expert testimony on whether the accused products actually operate with the specific phase relationship required by the claim.
  • Scope Questions: The claim requires the phase-difference condition to be met "when the vibration frequencies... is within a range of 2000 Hz to 3000 Hz." The parties may dispute whether this requires the condition to be met at all points within the range or only at certain frequencies.

V. Key Claim Terms for Construction

For the ’084 Patent:

• The Term: "the driving force being not parallel to a normal line of the housing panel"
• Context and Importance: This negative limitation is a core technical aspect of the invention. Its construction will be critical, as infringement depends on the geometric relationship between the transducer's force vector and the housing surface. Practitioners may focus on this term because the complaint's primary evidence is a simplified diagram (Compl. ¶33), the accuracy and interpretation of which will be debated.
• Intrinsic Evidence for Interpretation:
  • Evidence for a Broader Interpretation: The claim language itself is broad, only excluding a perfectly parallel orientation. The specification states that the angle between the driving force and the normal line "may be an acute angle," which covers any angle between 0 and 90 degrees, suggesting a wide scope of non-parallel arrangements could infringe (’084 Patent, col. 18:32-34).
  • Evidence for a Narrower Interpretation: The specification provides specific, preferred angular ranges (e.g., "33°~36°") and links them to achieving an optimal balance between low and high-frequency sound performance (’084 Patent, col. 19:16-19). A defendant may argue that the term should be narrowed to orientations that achieve this disclosed functional advantage.

For the ’582 Patent:

• The Term: "an absolute value of a difference between the first phase and the second phase is less than 60 degrees"
• Context and Importance: This term defines the central mechanism for the alleged sound leakage reduction. While the dispute may be primarily factual, its scope is key. Practitioners may focus on this term because the infringement analysis rests on complex technical measurements (Compl. ¶55), and any ambiguity in the claim's scope could be outcome-determinative.
• Intrinsic Evidence for Interpretation:
  • Evidence for a Broader Interpretation: The plain language of the claim requires the condition to be met whenever the frequency is within the specified 2000-3000 Hz range. The patent abstract describes the concept generally without further limitation (’582 Patent, Abstract).
  • Evidence for a Narrower Interpretation: While the specification does not appear to provide a basis for narrowing the "60 degrees" value, a defendant may argue that the term should be interpreted in light of the stated purpose of superimposing sound waves to "reduce an amplitude of the first leaked sound wave" (’582 Patent, col. 3:5-10). This could raise questions about whether trivial or momentary satisfaction of the 60-degree limit is sufficient for infringement if it does not result in meaningful sound reduction.

VI. Other Allegations

• Indirect Infringement: The complaint alleges inducement of infringement, stating that Defendants provide instruction manuals and online product listings with links to those manuals, which instruct end-users to operate the accused headphones in their normal, infringing manner (Compl. ¶¶15, 23, 46).
• Willful Infringement: The complaint alleges willful infringement for both patents. For the ’084 patent, it alleges Defendants had knowledge "at least as of the filing of this complaint" (Compl. ¶42). For the ’582 patent, it alleges Defendants "had or should have had the knowledge of the ’582 Patent before the filing of this complaint" (Compl. ¶76). This suggests the willfulness claim for the ’084 patent is based on post-suit conduct, while the claim for the ’582 patent is based on alleged pre-suit knowledge.

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

• A key evidentiary question will be one of technical proof: Can Plaintiff's testing data for the ’582 patent withstand scrutiny and prove that the accused products’ housing panels consistently maintain a vibration phase difference of less than 60 degrees across the 2-3 kHz frequency range, or will Defendant's counter-evidence reveal a fundamental mismatch in technical operation?
• A core issue for the ’084 patent will be one of functional interpretation: Does the diagrammatic evidence presented in the complaint accurately depict the force vector of the accused product’s transducer, and can this operation be definitively mapped to the claim limitation requiring a "driving force...not parallel to a normal line of the housing panel"?
• A third question will relate to culpability and damages: What evidence, if any, supports the allegation of pre-suit knowledge for the ’582 patent, and how will the differing allegations of knowledge for the two patents-in-suit impact the viability of the claims for willful infringement and potential enhanced damages?