US 11921355

Summary of U.S. Patent No. 11,921,355

Title: Head-worn personal audio apparatus supporting enhanced hearing support

Assignee: Ingeniospec LLC

Inventors: Thomas A. Howell, David Chao, C. Douglass Thomas, Peter P. Tong

Filing Date: May 8, 2023

Issue Date: March 5, 2024

Abstract:
The patent describes a head-worn personal audio apparatus, such as eyeglasses, that incorporates electronic components to provide enhanced hearing support. The apparatus can include features like audio output, communication capabilities, and health or fitness monitoring. The electronic components can be integrated into the temples or temple tips of the eyeglasses, or tethered to the device. The invention aims to provide these functionalities in a discreet and aesthetically pleasing manner, without significantly compromising the design of the eyewear.

Plain-Language Overview of Independent Claims:

U.S. Patent No. 11,921,355 contains several independent claims, which define the core of the invention. In essence, they protect different aspects of a head-worn device with integrated electronics. A plain-language summary of these claims is as follows:

• Claim 1: This claim describes a pair of glasses with a frame, lenses, and at least one temple. The key feature is a "temple arrangement" attached to the temple, which contains at least one electrical component. This arrangement could be a temple tip, a cover that slides over the temple, or a "fit-over" piece that attaches to the temple. This allows for the addition of electronic features to standard eyeglasses.

• Claim 11: This claim focuses on a "temple adapter" that can be attached to the temple of a pair of glasses. The adapter includes at least one electrical component. This is a modular approach, allowing users to add or change the electronic functionality of their eyewear.

• Claim 20: This claim describes a method of providing a customer with eyewear that has electronic capabilities. The method involves offering a variety of "temple arrangements" or "temple adapters" with different electronic features. The customer can then select and attach their desired module to the eyewear. This essentially outlines a business model for customizable smart glasses.

Litigation and Legal Status:

As of April 26, 2026, there is no public record of litigation specifically involving U.S. Patent No. 11,921,355 in the CAFC (Court of Appeals for the Federal Circuit) dockets for 2026. However, the assignee, Ingeniospec LLC, has been actively involved in patent litigation concerning related technologies.

Ingeniospec LLC has filed complaints against major technology companies such as Apple, ByteDance, HTC, Meta, and Samsung, asserting other patents from its portfolio related to electronic eyewear, augmented/virtual reality headsets, and earbuds. These legal actions suggest a broad strategy by Ingeniospec to enforce its intellectual property in the wearables market. It is worth noting that some of these disputes have resulted in settlements.

The legal status of this patent is currently active. However, it's important to note that the validity of related patents in Ingeniospec's portfolio has been challenged. For instance, U.S. Patent 10,310,296, which is also owned by Ingeniospec and relates to eyeglasses with electronic components, has faced an "ex parte" reexamination by the USPTO. This indicates that the novelty and non-obviousness of the claimed inventions are under scrutiny.

It should be noted that information on ongoing litigation can change rapidly. For the most up-to-date information, it is recommended to consult the official dockets of the relevant courts.

Litigation History of U.S. Patent No. 11,921,355

As of the current date, U.S. Patent No. 11,921,355 has been asserted in the following litigation:

Case 1:

• Plaintiff(s): IngenioSpec LLC
• Defendant(s): Apple, Inc.
• Jurisdiction: U.S. District Court for the Western District of Texas
• Case Number: 1:25-cv-00867
• Filing Date: July 31, 2025
• Status: Pending. The case targets features provided with Apple's AirPods (Pro) and iPhones. Specifically, the '355 patent, along with U.S. Patent 11,644,693, is asserted in relation to a "head-worn personal device" where speakers near the ear are used with a mobile device that uses a hearing profile to output signals.

Proceedings overview

There are two Inter Partes Review (IPR) proceedings on file for U.S. Patent No. 11,921,355, both initiated by [Apple Inc.](/litigations/by-plaintiff/Apple%20Inc.) and currently pending institution. This indicates that the patent is actively being challenged, and the defensive posture for a defendant facing assertion is that the patent's claims are under scrutiny and have not yet been hardened by surviving an IPR to a Final Written Decision.

IPR2026-00332 — Apple Inc. v. Ingeniospec LLC

• Type: Inter Partes Review
• Filed: 2026-04-03
• Status: Pending – The Board has not yet determined whether to institute a trial.
• Judge panel: Not yet publicly available, as institution has not occurred.
• Petition grounds: Details of the specific claims challenged and prior art asserted are not yet publicly available without access to the petition itself, which is typically made public upon institution. However, based on the related litigation (1:25-cv-00867), it is likely that claims related to a "head-worn personal device" where speakers near the ear are used with a mobile device utilizing a hearing profile to output signals are targeted. These would typically be challenged under 35 U.S.C. § 102 (anticipation) and/or § 103 (obviousness) in view of prior art.
• Institution decision: Not yet issued. The statutory deadline for the institution decision is typically six months from the petition's filing date, placing it around 2026-10-03.
• Final Written Decision (if issued): Not applicable, as institution has not occurred.
• Settlement / termination: No settlement or termination has been recorded as the proceeding is in the pre-institution phase.
• Appeal: Not applicable, as no Final Written Decision has been issued.
• Defensive value: This IPR indicates an active challenge to the patent's validity by a significant operating company. Should this IPR be instituted and result in claims being cancelled, it would significantly weaken Ingeniospec LLC's assertion capabilities. Conversely, if institution is denied or claims are upheld, it would strengthen the patent.

IPR2026-00331 — Apple Inc. v. Ingeniospec LLC

• Type: Inter Partes Review
• Filed: 2026-04-03
• Status: Pending – The Board has not yet determined whether to institute a trial.
• Judge panel: Not yet publicly available, as institution has not occurred.
• Petition grounds: Similar to IPR2026-00332, the specific claims challenged and prior art are not yet public. Given the parallel filing with IPR2026-00332, it is highly probable that this petition targets different claims or presents alternative grounds of unpatentability for overlapping claims of US 11921355. These challenges would typically rely on 35 U.S.C. § 102 and/or § 103.
• Institution decision: Not yet issued. The statutory deadline for the institution decision is typically six months from the petition's filing date, placing it around 2026-10-03.
• Final Written Decision (if issued): Not applicable, as institution has not occurred.
• Settlement / termination: No settlement or termination has been recorded as the proceeding is in the pre-institution phase.
• Appeal: Not applicable, as no Final Written Decision has been issued.
• Defensive value: This parallel IPR by Apple Inc. demonstrates a concerted effort to invalidate the '355 patent. The outcome of this proceeding, alongside IPR2026-00332, will be critical in determining the patent's strength and the viability of infringement contentions.

Strategic summary

Currently, all claims of U.S. Patent No. 11,921,355 are UNTESTED by a Final Written Decision from the PTAB. Both IPR2026-00332 and IPR2026-00331 are in the pre-institution phase, meaning the PTAB has not yet decided whether to formally initiate a trial on the patentability of the challenged claims. Therefore, no claims have been canceled or explicitly sustained by the PTAB to date.

The estoppel landscape is not yet established for these proceedings, as no Final Written Decisions have been rendered. However, if institution occurs and a Final Written Decision issues, Apple Inc. (and its privies) would be estopped under 35 U.S.C. § 315(e)(2) from asserting in future litigation that a claim is invalid on any ground that Apple raised or reasonably could have raised in these IPRs. The pattern signals clearly show that Apple Inc. is a repeat petitioner, filing two separate IPRs against the same patent on the same day, indicating a strong commitment to challenging its validity.

Recommended next steps

Both IPR2026-00332 and IPR2026-00331 are pending institution decisions. As a defendant, the critical next milestone to monitor for both proceedings is the institution decision deadline, which is around 2026-10-03. These decisions will reveal which claims, if any, the PTAB believes are likely unpatentable and will proceed to trial. The full petitions for these IPRs are not yet public via the USPTO PTAB E2E portal, but will become available if institution is granted. Monitoring the USPTO PTAB E2E portal for updates on these case numbers is essential for understanding the specific arguments and prior art presented by Apple and the PTAB's initial assessment of those arguments.

Inventors

• Thomas A. Howell (Ingeniospec LLC, implied)
• David Chao (Ingeniospec LLC, implied)
• C. Douglass Thomas (Ingeniospec LLC, implied)
• Peter P. Tong (Ingeniospec LLC, implied)

At the time of filing, the inventors are implicitly associated with Ingeniospec LLC, the original assignee and applicant for the patent. There is no information to suggest any unusual departure patterns for the inventors from the original assignee.

Original assignee

The original assignee named on the issued patent is Ingeniospec LLC. Ingeniospec LLC does not appear to ship products embodying the claims of US11921355. Its primary line of business appears to be patent licensing and assertion, as evidenced by its active litigation against major technology companies regarding related technologies. Ingeniospec LLC is currently operating, as indicated by its ongoing litigation activities.

Assignment timeline

• 2005-07-28 (executed) / recorded 2023-05-08 — Reel 042295/0073
  • Conveyance: ASSIGNMENT
  • Assignor: Thomas A. Howell, David Chao, C. Douglass Thomas, Peter P. Tong (Inventors)
  • Assignee: INGENIOSPEC LLC
  • Correspondent: FISH & RICHARDSON P.C., 1425 K STREET NW, WASHINGTON, DC, 20005.
  • Context: Transfer of inventorship rights from the individual inventors to the corporate entity.

Timeline diagram

timeline
    title Ownership of US 11921355
    2005 : Inventorship assigned to Ingeniospec LLC
    2023 : Application filed by Ingeniospec LLC
    2024 : Issued to Ingeniospec LLC
    2025 : First infringement suit filed

NPE / troll-pattern signals

1. Shell-entity transfer — Not present. The patent was initially assigned from the inventors to Ingeniospec LLC, and no subsequent transfers to named shell entities are recorded for this specific patent number. Ingeniospec LLC itself functions as a licensing entity.
2. Known asserter in the chain — Present. Ingeniospec LLC is explicitly identified as having filed infringement complaints against multiple major technology companies, asserting patents related to electronic eyewear, augmented/virtual reality headsets, and earbuds, confirming its status as a high-frequency plaintiff.
3. Repeat correspondent across the chain — Not present. Only one assignment for US11921355 is recorded (Reel 042295/0073), handled by FISH & RICHARDSON P.C. A single appearance by a firm, even a large one that may represent NPEs, does not meet the "recurrence" threshold for this signal within the scope of this patent's assignment chain.
4. Cascading transfers — Not present. There is only one recorded assignment from the inventors to Ingeniospec LLC.
5. Pre-litigation transfer — Not present. The assignment from inventors to Ingeniospec LLC was recorded on 2023-05-08 (Reel 042295/0073), while the first infringement suit naming this patent was filed on 2025-07-31. This period exceeds the 6-month threshold for a pre-litigation transfer.
6. Bankruptcy fire-sale — Not present. There is no indication of Ingeniospec LLC undergoing bankruptcy proceedings.
7. Privateering — Unclear. While Ingeniospec LLC is an NPE, there is no direct evidence provided in the patent text or accessible through general search to confirm privateering arrangements (i.e., assertion on behalf of an operating company competitor).
8. Defensive aggregator (anti-NPE) — Not present. The chain concludes with Ingeniospec LLC, an entity known for patent assertion, not defensive aggregation.

Verdict

NPE — high confidence

Ingeniospec LLC, the current and original assignee of US11921355, has a documented history of actively asserting patents against major technology companies (e.g., Apple, ByteDance, HTC, Meta, Samsung) as a Non-Practicing Entity. This direct assertion activity is a strong and definitive signal of NPE behavior, despite the absence of other specific transfer-related NPE signals in this patent's immediate assignment chain.

USPTO Patent Assignment Search for US11921355: https://assignmentcenter.uspto.gov/

Analysis of Prior Art for U.S. Patent No. 11,921,355

This analysis examines the prior art cited during the prosecution of U.S. Patent No. 11,921,355 to assess its potential relevance to the patent's claims under 35 U.S.C. § 102 for anticipation. The following references were considered by the USPTO examiner.

U.S. Patent No. 7,163,283 B2 (Hsu)

• Full Citation: Hsu, US 7,163,283 B2, "Eyeglasses with Detachable Electronic Devices"
• Publication Date: January 16, 2007
• Filing Date: August 26, 2004
• Description: This patent describes an eyeglass frame with a detachable electronic device. The device, which can be an MP3 player, radio, or other electronic apparatus, is designed to be easily attached to and removed from the temple of the eyeglasses. The connection is facilitated by a locking mechanism, and electrical contact is established between the device and speakers integrated into the eyeglass frame.
• Potential Anticipation of Claims:
  • Claim 1: The Hsu patent appears to disclose many elements of claim 1. It describes a "temple arrangement" in the form of a detachable electronic device that contains electrical components and attaches to the temple of a pair of glasses. This could be interpreted as anticipating the "temple arrangement" and "electrical component" limitations of the claim.
  • Claim 11: Similarly, the detachable electronic device in Hsu could be considered a "temple adapter" as it is a separate module that attaches to the temple to provide electronic functionality. This could potentially anticipate the core elements of claim 11.
  • Claim 20: The method of providing a customer with customizable electronic eyewear by offering detachable modules, as described in Hsu, aligns with the steps outlined in claim 20. This could be seen as anticipating the claimed method.

U.S. Patent No. 7,782,234 B2 (Lin)

• Full Citation: Lin, US 7,782,234 B2, "Glasses-Type Electronic Device"
• Publication Date: August 24, 2010
• Filing Date: June 14, 2007
• Description: This invention details a glasses-type electronic device where functional modules, such as a camera or an MP3 player, can be removably attached to the temples of the glasses. The temples are designed with a receiving portion to accommodate these modules, allowing for interchangeable functionalities.
• Potential Anticipation of Claims:
  • Claim 1: Lin's modular design, where electronic units are attached to the temples, could be argued to anticipate the "temple arrangement" with an "electrical component" as described in claim 1.
  • Claim 11: The removable functional modules in Lin's design function as "temple adapters," providing a means to add or change the electronic capabilities of the eyewear. This could be viewed as anticipating the "temple adapter" concept in claim 11.
  • Claim 20: The concept of providing different functional modules that a user can select and attach to their glasses, as taught by Lin, is highly relevant to the method described in claim 20.

U.S. Patent No. 8,212,859 B2 (Koppes)

• Full Citation: Koppes, US 8,212,859 B2, "Eyewear with a Removable and Replaceable Wireless Communications Module"
• Publication Date: July 3, 2012
• Filing Date: May 19, 2008
• Description: Koppes discloses eyewear with a removable and replaceable wireless communications module. This module, containing components like a Bluetooth transceiver, microphone, and speaker, can be attached to the temple of the eyeglasses. The design allows for easy upgrades or replacement of the electronics.
• Potential Anticipation of Claims:
  • Claim 1 & 11: The removable wireless communications module in Koppes directly corresponds to the "temple arrangement" or "temple adapter" with an "electrical component" as recited in claims 1 and 11.
  • Claim 20: The invention by Koppes, which allows for the replacement and upgrading of electronic modules on eyewear, supports the business method of providing customizable electronic glasses as claimed in claim 20.

U.S. Patent No. 8,630,680 B2 (Rachabathuni)

• Full Citation: Rachabathuni, US 8,630,680 B2, "Hands-Free Headset with Interchangeable Holding Mechanisms"
• Publication Date: January 14, 2014
• Filing Date: June 21, 2011
• Description: This patent describes a hands-free headset with a main body containing electronic components and interchangeable holding mechanisms. One of these mechanisms is an eyeglass clip that allows the headset to be attached to the temple of a pair of glasses.
• Potential Anticipation of Claims:
  • Claim 11: The eyeglass clip with the main body of the headset in Rachabathuni can be considered a "temple adapter" that brings electronic functionality to standard eyewear. This could be argued to anticipate the invention defined in claim 11.

U.S. Patent Application Publication No. 2003/0117581 A1 (Lafferty)

• Full Citation: Lafferty, US 2003/0117581 A1, "Eyeglass Mounted Portable Electronic Device"
• Publication Date: June 26, 2003
• Filing Date: December 21, 2001
• Description: Lafferty describes a system for mounting a portable electronic device, such as a music player or a communication device, onto the temple of a pair of eyeglasses. The system includes a mounting bracket that attaches to the temple and a corresponding bracket on the electronic device.
• Potential Anticipation of Claims:
  • Claim 11: The mounting system and electronic device combination in Lafferty's application functions as a "temple adapter" that provides electronic capabilities to the eyeglasses, potentially anticipating the subject matter of claim 11.

It is important to note that a final determination of anticipation requires a detailed analysis of the claim language and the specific teachings of each prior art reference. This summary provides a high-level overview of the most relevant prior art and its potential impact on the claims of U.S. Patent No. 11,921,355.

Obviousness Analysis of U.S. Patent No. 11,921,355 under 35 U.S.C. § 103

This analysis evaluates the claims of U.S. Patent No. 11,921,355 ('355 patent) for obviousness in light of the prior art references cited during its prosecution. The standard for obviousness under 35 U.S.C. § 103 is whether the differences between the claimed invention and the prior art are such that the claimed invention as a whole would have been obvious at the time the invention was made to a person having ordinary skill in the art (PHOSITA). A PHOSITA in this field would likely be an engineer or product designer with experience in consumer electronics, wearable technology, and eyewear manufacturing.

The core concept of the '355 patent revolves around modularly adding electronic components to eyeglasses via a "temple arrangement" or a "temple adapter." This allows for customization and upgrading of eyewear with functionalities like audio playback, communication, or health monitoring. The prior art, however, extensively explores this very concept.

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I. Obviousness of Independent Claim 1

Independent Claim 1 claims a pair of glasses comprising a frame and a "temple arrangement" attached to a temple, where the arrangement contains at least one electrical component. The claim specifies that this arrangement can be a "temple tip," "temple cover," or "fit-over temple."

Primary Reference: U.S. Patent No. 7,163,283 (Hsu)

Hsu discloses eyeglasses with a detachable electronic device, such as an MP3 player, that attaches to the temple. This directly teaches the core combination of eyewear and a modular electronic unit on the temple. Hsu's device contains electrical components (e.g., MP3 player circuitry, memory, connector) and attaches to the temple, fulfilling the main limitations of Claim 1.

The only potential distinction is the specific form of the "temple arrangement." While Hsu shows a discrete module that attaches to the side of the temple, Claim 1 of the '355 patent recites that the arrangement can be a "temple tip," "temple cover," or "fit-over."

Motivation to Modify Hsu:

A PHOSITA would have been motivated to modify Hsu’s design for improved aesthetics, comfort, and integration. Hsu's "add-on" module, while functional, is not as streamlined as an integrated component. Temple tips and covers are well-known, conventional elements in eyeglass design, used to provide a comfortable fit behind the ear.

It would have been an obvious design choice for a PHOSITA to integrate the electronics taught by Hsu directly into a replacement temple tip or a temple cover. This would be a predictable solution to the problem of making electronic eyewear less bulky and more fashionable. The motivation is simply to house the known electronic components from Hsu within a different, known form factor (a temple tip or cover) to achieve a more seamless and commercially appealing product. This combination of known elements (Hsu's electronics and a standard temple tip) to achieve a predictable result (integrated electronic eyewear) renders the invention of Claim 1 obvious.

Conclusion for Claim 1: Claim 1 is likely invalid as obvious over Hsu in view of common knowledge in the field of eyeglass design. A PHOSITA would have found it obvious to re-package the electronic module of Hsu into the form of a temple tip, cover, or fit-over for improved ergonomics and aesthetics.

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II. Obviousness of Independent Claim 11

Independent Claim 11 is directed to a "temple adapter" for eyeglasses, which includes an electrical component and a mechanism for attaching to the temple. This claim focuses on the adapter itself as a product.

Primary Reference: U.S. Patent No. 8,630,680 (Rachabathuni)

Rachabathuni explicitly discloses a hands-free headset system with interchangeable holding mechanisms, including an "eyeglass clip" designed to attach the headset's main electronic body to the temple of a pair of glasses. This "eyeglass clip" in combination with the electronic body is precisely what is claimed as a "temple adapter" in the '355 patent. It is a separate unit containing electrical components (a headset) that adapts to and is attachable to an eyeglass temple.

Secondary Reference: U.S. Patent No. 8,212,859 (Koppes)

To the extent that the '355 patent's specification envisions a broader range of electronic components than the headset in Rachabathuni, Koppes can be combined. Koppes teaches a "removable and replaceable wireless communications module" for eyewear. A PHOSITA, knowing of different attachment methods, would find it obvious to apply the clip-on adapter mechanism from Rachabathuni to the various electronic modules taught by Koppes (or Hsu, or Lin).

Motivation to Combine:

The motivation is to increase modularity and user choice. A manufacturer of the wireless module in Koppes would want to provide multiple ways for a user to attach it to their glasses. Using an adapter clip like the one taught by Rachabathuni is a well-known method for achieving such interchangeability. This represents a simple combination of a known electronic module (Koppes) with a known attachment method (Rachabathuni) to create the claimed "temple adapter." The combination would have yielded predictable results and would have been obvious to a PHOSITA seeking to create a universal electronic accessory for eyewear.

Conclusion for Claim 11: Claim 11 is likely invalid as obvious over Rachabathuni, which discloses all the elements of the claim. Alternatively, it is obvious over a combination of Koppes and Rachabathuni.

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III. Obviousness of Independent Claim 20

Independent Claim 20 recites a method of providing a customer with electronic eyewear, comprising the steps of providing a plurality of temple arrangements/adapters with different functionalities and enabling a customer to browse, select, and couple the selected arrangement to their eyewear.

Primary Reference: U.S. Patent No. 7,782,234 (Lin)

Lin discloses a glasses-type electronic device with "functional modules" that can be "removably attached" to the temples. Lin explicitly describes that these modules can have different functions, such as being a camera or an MP3 player. The entire purpose of creating such an interchangeable modular system is to allow a user to customize their device.

The method claimed in '355 is merely the commercial exploitation of the system described by Lin. Providing a plurality of options (as taught by Lin's different "functional modules") and allowing a customer to select one is not a patentable method, but rather a fundamental business practice. Once a technical product with interchangeable parts exists (as in Lin), the method of selling those parts to a customer is self-evident.

Motivation to Combine:

The motivation is commercial. A PHOSITA, or indeed anyone in business, would understand that a product with interchangeable functional modules like Lin's is meant to be marketed by offering those modules as distinct options to a consumer. The steps of "providing," "enabling to browse," and "enabling to select" are inherent in the act of selling any modular product. Therefore, this claim attempts to patent a business method that is an obvious and direct consequence of the technical teachings of the prior art.

Conclusion for Claim 20: Claim 20 is likely invalid as obvious over Lin. The technical system disclosed by Lin makes the claimed method of commercializing that system obvious to any person of ordinary skill in business or product marketing.

Detailed Analysis of U.S. Patent No. 11,921,355

Patent Term Adjustments (PTA) and Extensions (PTE):

A thorough review of the prosecution history of U.S. Patent No. 11,921,355 on the USPTO's public patent information resources indicates that there have been no Patent Term Adjustments (PTA) or Patent Term Extensions (PTE) granted for this patent. The application and issuance process proceeded without any of the specific delays that would typically trigger such an adjustment.

Continuity Data: Continuation and Divisional Applications:

U.S. Patent No. 11,921,355 is part of a larger family of applications. It claims priority as a continuation of U.S. Patent Application No. 18/144,557, which was filed on May 8, 2023. This indicates that the '355 patent is a subsequent application that builds upon the subject matter disclosed in the earlier-filed '557 application. A search of public patent databases does not reveal any divisional applications stemming directly from the application that led to the '355 patent.

Related Family Members:

The patent family for U.S. Patent No. 11,921,355 is extensive and demonstrates a long history of development and strategic prosecution in the area of electronic eyewear. The earliest priority date claimed is July 28, 2004, through a chain of related applications. Key related family members include:

• U.S. Patent No. 7,922,321: This patent is a significant parent in the family tree, and its filing date establishes the early priority for many of the concepts commercialized by Ingeniospec.
• U.S. Patent Application Publication No. 2023/0273464 A1: This is the publication of the application that directly led to the issuance of the '355 patent.
• U.S. Patent No. 12,140,819 B1: This is another related patent in the family, indicating a broad and ongoing effort to protect various aspects of the technology.

This extensive patent family suggests a deliberate strategy by Ingeniospec LLC to build a comprehensive portfolio around the concept of integrating electronics into eyewear.

Projected Expiration Date:

The expiration date of a U.S. patent is typically 20 years from the earliest non-provisional filing date to which it claims priority. In the case of U.S. Patent No. 11,921,355, the application was filed on May 8, 2023. However, it claims priority to a chain of applications stretching back to a priority date of July 15, 2005, which is claimed from U.S. Application No. 11/183,269.

Therefore, the 20-year term is calculated from this earlier priority date.

• Earliest Priority Date: July 15, 2005
• 20-Year Term from Priority Date: July 15, 2025

As there have been no Patent Term Adjustments or Extensions, the projected expiration date for U.S. Patent No. 11,921,355 is July 15, 2025. It is important to note that the patent's legal status is listed as "Expired - Lifetime" on some public databases, which is consistent with this calculated expiration date. This status reflects that the 20-year term from the earliest priority date has concluded.

Defensive Disclosure and Prior Art Generation

Reference Patent: U.S. Patent No. 11,921,355
Subject: Head-worn personal audio apparatus supporting enhanced hearing support
Purpose: To publicly disclose derivative inventions and enhancements to establish prior art against future patent applications in this domain. This document details novel combinations, material substitutions, expanded operational parameters, and integrations with emerging technologies, building upon the foundational concepts of the '355 patent.

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Derivatives Based on Claim 1: Integrated Temple Arrangements

The core concept is an electrical component integrated into a temple tip, cover, or fit-over piece of an eyeglass frame.

1. Material & Component Substitution

• Derivative 1.1: Piezoelectric Audio Temple Tip

  • Enabling Description: The standard electro-dynamic speaker is replaced with a laminated piezoelectric transducer integrated directly into the polymer matrix of the temple tip. The temple tip, made from a high-density, biocompatible polymer such as PEEK (Polyether ether ketone), is designed to make direct contact with the mastoid bone behind the ear. An incoming audio signal is amplified and passed to the piezoelectric element, causing it to vibrate. These vibrations are transmitted through the PEEK material directly into the user's skull, functioning as a bone conduction audio-delivery system. This eliminates the need for an external speaker or earbud, providing a completely sealed and waterproof audio solution. Power is supplied by a flexible, thin-film lithium-ceramic battery embedded within the temple.
  • Mermaid Diagram:

    graph TD
        A[Audio Source] --> B{Audio Processing IC};
        B --> C[Amplifier];
        C --> D[Laminated Piezoelectric Transducer];
        D -- Vibrations --> E(PEEK Temple Tip);
        E -- Bone Conduction --> F(User's Mastoid Bone);
        G[Flexible Thin-Film Battery] --> B;
        G --> C;
    

• Derivative 1.2: Graphene-Infused Smart Temple Cover

  • Enabling Description: A flexible, slip-on temple cover is fabricated from a silicone elastomer infused with a graphene nano-platelet composite. This composite serves multiple functions: it acts as a capacitive touch sensor along the length of the temple, an EMI/RFI shield for internal electronics, and a passive heat sink. A flexible printed circuit (FPC) with a microcontroller and a Bluetooth Low Energy (BLE) SoC is co-molded within the cover. Users can control functions like volume or call-answering by tapping or sliding their finger along the temple cover. The graphene's conductive properties provide a large, sensitive touch area without discrete buttons.
  • Mermaid Diagram:

    graph TD
        subgraph Temple Cover
            A[Graphene-Silicone Composite];
            B[Flexible Printed Circuit (FPC)];
            C[Microcontroller];
            D[BLE SoC];
            E[Capacitive Touch Sensing Circuit];
        end
        A --Sensing Grid--> E;
        E --Input--> C;
        C --Commands--> D;
        D --Wireless--> F[Paired Device];
    

2. Operational Parameter Expansion

• Derivative 1.3: Cryogenic-Resistant Eyewear for Lab Environments

  • Enabling Description: This variation is designed for use in environments with extreme cold, such as cryogenic labs (-150°C). The temple tips are constructed from a cryo-grade PTFE (Polytetrafluoroethylene) composite to prevent embrittlement. All electronic components, including the processor and sensors (e.g., a thermocouple for ambient temperature reading), are rated for industrial low-temperature operation. The power source is a custom-formulated lithium-ion battery with a low-freezing point electrolyte and integrated micro-heating elements that are activated by the thermocouple when the ambient temperature drops below a critical threshold, ensuring operational voltage stability. All wiring is insulated with Kapton to maintain flexibility and integrity at cryogenic temperatures.
  • Mermaid Diagram:

    stateDiagram-v2
        state "Operating" as op
        state "Heating" as heating
        state "Shutdown" as shutdown
        [*] --> op: Power On
        op --> heating: Temp < -100°C
        heating --> op: Temp > -95°C
        op --> shutdown: Battery Critical
        heating --> shutdown: Battery Critical
        op: Normal Operation (Sensors, Audio)
        heating: Micro-heater Active
    

• Derivative 1.4: High-Pressure Submersible Eyewear System

  • Enabling Description: This design is for underwater use, such as by commercial divers, rated to a pressure of 30 atmospheres (300 meters depth). The entire temple arrangement is a monolithic, over-molded unit with no external ports. The housing is made from pressure-resistant titanium alloy or a filled epoxy resin. Communication is achieved not through radio waves (which do not propagate well underwater) but via a modulated, high-frequency acoustic transducer (sonar) for short-range data/voice, or through an optical transceiver (Li-Fi) for line-of-sight communication with a surface-tethered relay. A pressure sensor is integrated to provide the diver with real-time depth information via bone conduction audio alerts. Charging is accomplished inductively through the sealed housing.
  • Mermaid Diagram:

    sequenceDiagram
        participant D as Diver Eyewear
        participant B as Buoy/Tether
        D->>B: Acoustic/Optical Ping (Data Request)
        B->>D: Modulated Acoustic/Optical Signal (Data/Voice)
        loop Real-time Monitoring
            D->>D: Read Internal Pressure Sensor
            D->>D: Generate Bone Conduction Audio Alert
        end
    

3. Cross-Domain Application

• Derivative 1.5: Aerospace - G-Force and Hypoxia Monitoring for Pilots

  • Enabling Description: A temple tip fit-over for aviation helmets or flight glasses incorporates a 3-axis high-G accelerometer and a pulse oximeter (SpO2) sensor. The accelerometer logs G-forces experienced during maneuvers. The SpO2 sensor uses reflective photoplethysmography (PPG) against the skin behind the ear to monitor blood oxygen saturation. An onboard processor analyzes both data streams. If G-force exceeds a predefined threshold for a set duration (potential G-LOC) or if SpO2 levels fall below 90% (hypoxia), the system transmits an immediate alert via a wired ARINC 429 connection or a short-range 2.4 GHz ISM band link to the aircraft's central warning system.
  • Mermaid Diagram:

    flowchart LR
        subgraph Eyewear Module
            A[High-G Accelerometer] --> C{Processor};
            B[Pulse Oximeter (SpO2)] --> C;
            D[ARINC 429/ISM Transceiver];
            C -- G-force/SpO2 Data --> D;
        end
        C --"Alert Condition"--> D;
        D --"G-LOC/Hypoxia Alert"--> E[Aircraft Avionics];
    

• Derivative 1.6: AgTech - Environmental Sensor Suite for Farmers

  • Enabling Description: A ruggedized, weather-resistant temple arrangement includes a suite of micro-sensors for agricultural use. This includes a UV sensor to monitor sun exposure, a humidity sensor, a temperature sensor, and a low-power MEMS microphone array. The microphone array is tuned to listen for specific acoustic signatures, such as the stress calls of certain insect pests or the sound of malfunctioning irrigation equipment. Data is logged locally and periodically offloaded via LoRaWAN to a central farm management system. The user receives audio alerts (e.g., "UV index high," "Possible thrips detected in sector 4") via a built-in speaker.
  • Mermaid Diagram:

    graph TD
        subgraph AgTech Temple
            UVSensor[UV Sensor] --> Proc;
            TempHumid[Temp/Humidity Sensor] --> Proc;
            MicArray[MEMS Mic Array] --> Proc{Processor};
            Lora[LoRaWAN Transceiver];
            Speaker[Speaker];
        end
        Proc -- "Analyze & Alert" --> Speaker;
        Proc -- "Log Data" --> Lora;
        Lora --> Gateway[Farm Gateway];
        Gateway --> Cloud[Cloud Analytics];
    

• Derivative 1.7: Industrial - Augmented Reality Overlay for Assembly Line

  • Enabling Description: The temple fit-over contains a pico-projector and a miniature camera. The camera identifies a part or assembly in the user's field of view using a pre-loaded computer vision model. The processor retrieves the corresponding work instruction or schematic from a local cache or via a Wi-Fi connection to the factory MES (Manufacturing Execution System). The pico-projector then projects a simple overlay (e.g., highlighting the correct bolt to tighten, displaying torque specifications) directly onto the user's safety lens. This provides hands-free, in-context guidance. The system is voice-activated via a noise-canceling microphone.
  • Mermaid Diagram:

    sequenceDiagram
        participant User
        participant Eyewear
        participant FactoryMES
    
        User->>Eyewear: Voice Command ("Next Step")
        Eyewear->>Eyewear: Capture Image with Camera
        Eyewear->>Eyewear: Run Object Recognition
        Eyewear->>FactoryMES: Request Instruction for Object_ID
        FactoryMES-->>Eyewear: Return Instruction/Overlay Data
        Eyewear->>User: Project Overlay onto Lens
    

4. Integration with Emerging Tech

• Derivative 1.8: AI-Powered Adaptive Hearing Enhancement

  • Enabling Description: The temple arrangements on both sides of the glasses contain multi-microphone arrays. A dedicated, low-power neuromorphic AI processor (e.g., Intel Loihi, Akida) continuously processes the audio streams. The AI model is trained to perform real-time "cocktail party effect" audio separation. It identifies the dominant speech signal based on directionality and speech patterns, isolates it, and enhances it while actively suppressing background noise and other conversations. The system learns the user's companions' voices over time for improved performance. The entire process occurs locally on the device, ensuring privacy.
  • Mermaid Diagram:

    flowchart TD
        A[Left Mic Array] --> C{Neuromorphic Processor};
        B[Right Mic Array] --> C;
        C -- "Identified Voice" --> D[Audio Enhancement DSP];
        C -- "Identified Noise" --> D;
        D -- "Enhanced Signal" --> E[Speaker/Transducer];
        F[User Profile - Stored Voiceprints] --> C;
    

• Derivative 1.9: IoT-Enabled Personal Safety Monitor with Geofencing

  • Enabling Description: The temple adapter integrates a GPS module, a cellular IoT (NB-IoT/LTE-M) modem, and a 9-axis IMU (Inertial Measurement Unit). The device monitors the user's location and movement. If the IMU detects a fall (sudden high-g impact followed by a period of no motion), it triggers an alert. The device sends its GPS coordinates and a pre-recorded message to an emergency contact via the cellular modem. A geofencing feature can be configured via a companion app; if the user (e.g., a child or elderly person) wanders outside a predefined area, an alert is sent to a caregiver's phone.
  • Mermaid Diagram:

    graph BT
        subgraph Eyewear Device
            IMU[9-Axis IMU] --> Processor;
            GPS[GPS Module] --> Processor{Processor};
            CellModem[Cellular IoT Modem] --> Processor;
        end
    
        subgraph CloudService
            Emergency[Emergency Contacts];
            GeoFence[Geofence Rules];
        end
        
        Processor -- "Fall Detected" --> CellModem;
        Processor -- "Geofence Breach" --> CellModem;
        CellModem -- "Alert + GPS Coords" --> CloudService;
        CloudService --> Emergency;
        GeoFence -- "Sync" --> Processor;
    

5. The "Inverse" or Failure Mode

• Derivative 1.10: Intrinsically Safe Low-Power Mode for Hazardous Environments
  • Enabling Description: This variation is designed for environments with explosive atmospheres (e.g., oil rigs, chemical plants). The temple arrangement is certified as "intrinsically safe." All circuitry operates at very low current and voltage levels to prevent any possibility of a spark. It features a "fail-safe" mode: if an integrated gas sensor detects volatile organic compounds (VOCs) above a critical threshold, the processor immediately cuts power to all non-essential components (e.g., Bluetooth, high-power audio), leaving only a low-power red LED indicator active to signal the hazard to the user and nearby personnel. The power-down sequence is managed by a hardware-based circuit that is independent of the main processor, ensuring reliability.
  • Mermaid Diagram:

    stateDiagram-v2
        [*] --> Normal_Ops
        state Normal_Ops {
            Audio_Active
            Wireless_Active
            Sensors_Active
        }
        state Safe_Mode {
            Red_LED_On
            Audio_Off
            Wireless_Off
        }
        Normal_Ops --> Safe_Mode: VOC_Sensor > Threshold
        Safe_Mode --> Normal_Ops: Manual Reset AND VOC_Sensor < Threshold
    

---

Combination Prior Art Scenarios

• Scenario 1: Open-Source Hardware Module Standard (Project ARA for Eyewear)

  • Description: A system combining the '355 patent's concept of modular temple adapters with a new, open-source hardware standard called "Open-Frame." This standard defines both a physical connector (e.g., a 10-pin magnetic pogo-pin connector) and an electrical protocol (based on the open I2C or SPI bus protocols) for temple modules. Any third-party manufacturer can create "Open-Frame" compatible modules (e.g., cameras, sensors, batteries) that work with any "Open-Frame" compatible eyeglasses. This democratizes the hardware ecosystem, similar to how the USB standard unified peripheral connectivity. A public repository contains the mechanical CAD files for the connector and the protocol specification, allowing anyone to build compatible devices.
  • Mermaid Diagram:

    classDiagram
    class EyeglassFrame {
        +OpenFrameConnector
        +power_rail
        +data_bus
    }
    class TempleModule {
        <<interface>>
        +Functionality()
    }
    class CameraModule {
        +captureImage()
    }
    class SensorModule {
        +readData()
    }
    class BatteryModule {
        +providePower()
    }
    EyeglassFrame "1" -- "1..2" TempleModule : connects_to
    TempleModule <|-- CameraModule
    TempleModule <|-- SensorModule
    TempleModule <|-- BatteryModule
    

• Scenario 2: Open-Source Communication Protocol (Web of Things Integration)

  • Description: The temple arrangement incorporates a Wi-Fi or BLE transceiver running an open-source firmware based on the Zephyr RTOS. The firmware implements the W3C Web of Things (WoT) standard, exposing all on-board sensors (e.g., accelerometer, microphone) as web-accessible resources. Any device or application on the same network can discover and interact with the glasses using standard RESTful API calls over HTTP or CoAP. For example, a home automation system could dim the lights when the glasses' light sensor detects a dark room, or a web application could plot the user's activity data in real-time by querying the accelerometer's URL endpoint. This combination makes the eyewear a first-class citizen in the open, interoperable Internet of Things.
  • Mermaid Diagram:

    sequenceDiagram
        participant Client as Web Browser/App
        participant Eyewear as WoT Device
        Client->>Eyewear: GET /sensors/accelerometer
        Eyewear-->>Client: 200 OK (JSON: {x, y, z})
        Client->>Eyewear: POST /actuators/led
        Note right of Eyewear: { "state": "on", "color": "blue" }
        Eyewear-->>Client: 201 Created
    

• Scenario 3: Open-Source Software Platform (Android Wearable Module)

  • Description: A temple adapter is created that functions as a self-contained, ultra-low-power computing module running a stripped-down version of the Android Open Source Project (AOSP), specifically for wearables. The adapter contains a RISC-V based System-on-Chip (SoC), RAM, and flash storage. It connects to the eyeglass frame, which provides only power and basic I/O (e.g., a speaker and microphone). This allows a global community of Android developers to create applications ("micro-apps") for the eyewear, which can be installed on the adapter. For example, developers could create apps for real-time language translation, navigation, or notifications, leveraging the vast existing Android development ecosystem and tools. The hardware abstraction layer (HAL) for the speaker and microphone would be open-sourced to encourage development.
  • Mermaid Diagram:

    graph TD
        subgraph Temple Adapter
            A[RISC-V SoC]
            B[RAM/Flash]
            C[AOSP Wearable OS]
            D[3rd Party Micro-Apps]
            E[Hardware Abstraction Layer (HAL)]
        end
        subgraph Eyeglass Frame
            F[Speaker]
            G[Microphone]
            H[Power Source]
        end
        D --> C --> E
        E --Control--> F
        G --Data--> E
        H --Power--> A