Encryptpat LLC v. Google LLC

I. Executive Summary and Procedural Information

• Parties & Counsel:
  • Plaintiff: EncryptPat, LLC (Virginia)
  • Defendant: Google LLC (Delaware)
  • Plaintiff's Counsel: Devlin Law Firm LLC
• Case Identification: 7:26-cv-00227, W.D. Tex., 08/21/2026
• Venue Allegations: Venue is alleged to be proper in the Western District of Texas because Google has a regular and established place of business in Austin, where it employs numerous people, conducts research and development related to the accused products, and operates a retail store that sells the accused products.
• Core Dispute: Plaintiff alleges that Defendant's Google Pixel phones and Pixel Watches, through features like "Watch Unlock," infringe four patents related to securing handheld devices using a paired, body-mounted wireless component.
• Technical Context: The technology concerns using a wearable device, like a smartwatch, to automatically unlock a paired smartphone when in close proximity and lock it when separated, aiming to improve user convenience and security.
• Key Procedural History: The four asserted patents claim priority back to a 2006 application and are part of a larger family of patents from inventor Charles M. Leedom, Jr. The complaint notes that the inventor holds over 30 patents, none of which have ever been found invalid. No prior litigation or post-grant proceedings are mentioned in the complaint.

Case Timeline

Date	Event
2006-06-26	Earliest Priority Date for '366, '265, '385, and '913 Patents
2022-06-28	U.S. Patent No. 11,375,366 Issues
2023-04-04	U.S. Patent No. 11,622,265 Issues
2023-05-09	U.S. Patent No. 11,647,385 Issues
2024-06-18	U.S. Patent No. 12,015,913 Issues
2025-05-01	Google opens Google Store in Austin, Texas (approx. date)
2026-08-21	Complaint Filing Date

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

U.S. Patent No. 11,375,366 - "Security System for Handheld Wireless Devices Using Time-Variable Encryption Keys"

• Patent Identification: U.S. Patent No. 11,375,366, "Security System for Handheld Wireless Devices Using Time-Variable Encryption Keys," issued June 28, 2022.
• The Invention Explained:
  • Problem Addressed: The patent's background section describes the security vulnerabilities of portable wireless devices at the time of the invention (c. 2006) Compl. ¶17 It notes that reliance on user-entered passwords was often ineffective because users disabled them for convenience, and that more secure methods like public key infrastructure (PKI) were too cumbersome for widespread mobile adoption, leaving lost or stolen devices exposed '366 Patent, col. 1:14-24 '366 Patent, col. 2:53-62
  • The Patented Solution: The invention proposes a two-component system to solve this problem '366 Patent, abstract The first component is a "body mounted key generating component" (e.g., a watch or wristband) that wirelessly broadcasts time-variable secret or private encryption keys within a user's immediate vicinity Compl. ¶18 The second is a "handheld wireless component" (e.g., a smartphone) that receives these keys to enable its functions. If the handheld is separated from the body-mounted component, it automatically becomes inoperable, thus securing the device without requiring active user input '366 Patent, col. 7:29-46
  • Technical Importance: This approach provided a practical method for automating device security based on physical proximity to the authorized user, enhancing both security and convenience over existing methods Compl. ¶18
• Key Claims at a Glance:
  • The complaint specifically asserts infringement of at least claim 1 of the '366 patent Compl. ¶44
  • Independent claim 1 of the '366 Patent recites a system comprising:
    • A "key generating component" adapted to be mounted on an individual's body for wirelessly transmitting, within the immediate proximity of the individual, a key signal comprising secret or private key information corresponding to time variable secure key information.
    • A "handheld wireless component," physically separated from the key generating component, adapted to wirelessly receive the key signal, use the key information to encrypt a message, and transmit the encrypted message to a third party.
    • The key generating component includes a processor adapted to generate a time variable key.
  • The complaint does not explicitly reserve the right to assert other claims, but this is standard practice.

U.S. Patent No. 11,622,265 - "Security System for Handheld Wireless Devices Using Time-Variable Encryption Keys"

• Patent Identification: U.S. Patent No. 11,622,265 B2, "Security System for Handheld Wireless Devices Using Time-Variable Encryption Keys," issued April 4, 2023.
• The Invention Explained:
  • Problem Addressed: The '265 Patent addresses the same problems as its parent '366 patent: the trade-off between security and convenience in portable wireless devices, where password protection was often bypassed by users and more robust cryptographic systems were too complex for mainstream adoption '265 Patent, col. 1:29-44
  • The Patented Solution: The '265 Patent claims a "wrist mountable component" (e.g., a smartwatch) that enables a paired "smartphone" to perform certain functions, such as wireless communication, only when the two devices are within each other's vicinity '265 Patent, abstract '265 Patent, claim 1 The component includes a "secret key circuit" and a wireless transceiver to broadcast an encrypted signal that the smartphone uses for this enabling/disabling function. If the smartphone is outside the vicinity, it becomes "incapacitated" from performing those functions '265 Patent, col. 28:19-27
  • Technical Importance: This patent specifies the now-common form factor of a wrist-worn device paired with a smartphone, providing a concrete technical blueprint for proximity-based security in that popular consumer electronics paradigm Compl. ¶21
• Key Claims at a Glance:
  • The complaint specifically asserts infringement of at least claim 1 of the '265 patent Compl. ¶55
  • Independent claim 1 of the '265 Patent recites a "wrist mountable component" for enabling a smartphone, comprising:
    • A band for mounting the component on a user's wrist.
    • A "secret key circuit" for forming an encrypted signal in accordance with a second encryption algorithm using a secret key available to both the wrist component and the smartphone.
    • A wireless transceiver for broadcasting the encrypted signal.
    • The operation of the circuit and transceiver enables the smartphone to perform functions when in the vicinity and "incapacitated for performing said functions" when outside the vicinity.
  • The complaint does not explicitly reserve the right to assert other claims.

U.S. Patent No. 11,647,385 - "Security System for Handheld Wireless Devices Using Time-Variable Encryption Keys"

• Patent Identification: U.S. Patent No. 11,647,385 B1, "Security System for Handheld Wireless Devices Using Time-Variable Encryption Keys," issued May 9, 2023.
• Technology Synopsis: This patent, from the same family, focuses on the smartphone side of the system. It claims a smartphone configured to be enabled by a signal from a wrist-mountable component, where the smartphone itself contains the circuitry to implement a primary encryption algorithm (e.g., for communicating with remote servers) and is enabled or disabled from doing so based on receiving a secondary encrypted signal from the paired wearable over a wireless link '385 Patent, abstract '385 Patent, claim 1
• Asserted Claims: The complaint asserts at least claim 1 Compl. ¶66
• Accused Features: The accused features are the automatic lock and unlock functionalities of Google Pixel phones when paired with Google Pixel Watches, marketed under names like "Watch Unlock" and "Smart Lock" Compl. ¶33 Compl. ¶¶57-67

U.S. Patent No. 12,015,913 - "Security System for Handheld Wireless Devices Using Time-Variable Encryption Keys"

• Patent Identification: U.S. Patent No. 12,015,913 B2, "Security System for Handheld Wireless Devices Using Time-Variable Encryption Keys," issued June 18, 2024.
• Technology Synopsis: This patent also claims the smartphone component of the system. It describes a smartphone with "special platform circuitry optimized for public key encryption" that is enabled to perform functions when it receives an encrypted signal from a paired, wrist-mounted component over a "short range wireless link." The smartphone is disabled from performing these functions if it fails to receive the signal, such as when it is separated from the wrist-mounted component '913 Patent, abstract '913 Patent, claim 1
• Asserted Claims: The complaint asserts at least claim 1 Compl. ¶67 [sic, likely ¶77]
• Accused Features: The accused features are the automatic lock and unlock functionalities of Google Pixel phones when paired with Google Pixel Watches, marketed under names like "Watch Unlock" and "Smart Lock" Compl. ¶33 Compl. ¶¶68-78

III. The Accused Instrumentality

Product Identification

The complaint identifies the Accused Instrumentalities as Google's mobile electronic devices, including "mobile smartphones and smartwatches, such as those marketed under the GOOGLE PIXEL® brand" Compl. ¶26 Compl. ¶33 Specifically, Google Pixel phones and Pixel Watches are named Compl. ¶11

Functionality and Market Context

The complaint alleges that the accused products include specialized hardware and software that enable features marketed as "SMART LOCK," "WATCH UNLOCK," "LOCK PHONE WHEN LEFT BEHIND," "NEARBY UNLOCK," and "EXTEND UNLOCK" Compl. ¶33 These features are alleged to automatically lock or unlock a smartphone based on communications with a paired smartwatch Compl. ¶33 The complaint states that Google encourages and teaches customers to use these features through its marketing and online support materials Compl. ¶34 Plaintiff alleges that Google has derived "revenues... of hundreds of millions of dollars" from the unauthorized use of the inventions Compl. ¶26

IV. Analysis of Infringement Allegations

The complaint references claim chart exhibits that are not provided with the filing (Compl. ¶44; Compl. ¶55; Compl. ¶66; Compl. ¶67 [sic]). In the absence of these exhibits, the infringement theory is summarized below based on the narrative allegations.

The central infringement theory is that the combination of a Google Pixel Watch (the "wearable") and a Google Pixel phone (the "handheld") practices the claims of the Asserted Patents Compl. ¶11 Compl. ¶18 The complaint alleges that the Pixel Watch functions as the claimed "body mounted key generating component" or "wrist mountable component," while the Pixel phone functions as the claimed "handheld wireless component" or "smartphone" Compl. ¶18 Compl. ¶33

The "Watch Unlock" and "Smart Lock" features are alleged to implement the claimed invention by having the Pixel Watch wirelessly communicate with the Pixel phone to automatically unlock it when the user is nearby and wearing the watch, and to automatically lock the phone when it is separated from the watch Compl. ¶33 This functionality is alleged to meet the claim limitations requiring a wearable device to wirelessly transmit a key or signal that enables or disables secure functions on a paired handheld device based on proximity '366 Patent, claim 1 '265 Patent, claim 1

No probative visual evidence provided in complaint.

• Identified Points of Contention:
  • Scope Questions: The patents describe a system deeply integrated with a "certification authority" and "time variable" keys, suggestive of a formal Public Key Infrastructure (PKI) '366 Patent, abstract A potential point of contention is whether the accused "Watch Unlock" feature, which may rely on standard Bluetooth proximity detection, performs the specific cryptographic functions recited in the claims, or if it is merely a proximity-based convenience feature outside the claimed invention's scope.
  • Technical Questions: The infringement analysis may turn on the technical details of how Google's features operate. A key question is what evidence exists that the accused system uses "time variable secure key information" as described in the patents, rather than a static pairing key or simple presence detection. The complaint does not provide technical evidence on this point, instead citing marketing materials Compl. ¶33

V. Key Claim Terms for Construction

For U.S. Patent No. 11,375,366

• The Term: "key generating component"
• Context and Importance: This term defines the wearable device. Its construction is critical because it determines the functions the accused Pixel Watch must perform to infringe. Practitioners may focus on whether "generating" requires more than simply storing and transmitting a pre-existing key.
• Intrinsic Evidence for Interpretation:
  • Evidence for a Broader Interpretation: The specification describes the component's form factor broadly, including a "wristwatch, wristband, bracelet, ring, patch... or even mounted subcutaneously," which may support construing the term to cover any body-worn device performing the claimed function '366 Patent, col. 11:7-10
  • Evidence for a Narrower Interpretation: The abstract and detailed description repeatedly link the component to a "certification authority" and the generation of "time variable secure key information" under its control '366 Patent, abstract '366 Patent, col. 7:56-62 This could support a narrower construction requiring the component to be part of a formal, managed cryptographic system that actively generates new keys over time, not just transmit a signal.

For U.S. Patent No. 11,622,265

• The Term: "incapacitated for performing said functions"
• Context and Importance: This phrase defines the state of the smartphone when it is separated from the wearable. The degree of "incapacitation" required by the claim will be a central issue for determining infringement.
• Intrinsic Evidence for Interpretation:
  • Evidence for a Broader Interpretation: The term could be interpreted broadly to mean any state where the user is prevented from using the phone's main features, such as a standard screen lock. The claim language itself does not specify the degree of incapacitation.
  • Evidence for a Narrower Interpretation: The specification provides a more specific example, stating the inactivation "could be limited to use of the phone to make outgoing calls or send other type outgoing messages but allow incoming calls to be received so that the user could still call her phone should it be misplaced" '265 Patent, col. 12:2-7 This may support a narrower construction requiring a selective disabling of specific functions rather than a complete lockout.

VI. Other Allegations

• Indirect Infringement: The complaint alleges both induced and contributory infringement for all four asserted patents (e.g., Compl. ¶38; Compl. ¶49). Inducement is based on allegations that Google "actively encourages and instructs" customers to use the accused features through its "marketing and online support" Compl. ¶34 Compl. ¶41 Contributory infringement is based on the allegation that the accused software and hardware components have "no commercially significant use other than to enable the infringing features" Compl. ¶39 Compl. ¶50
• Willful Infringement: Willfulness is alleged for all four patents. The allegations are based on knowledge "at least as of the date of this Complaint," suggesting a theory of post-suit willfulness, and state that Google has been "willfully blind" to its infringement (e.g., Compl. ¶41; Compl. ¶52).

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

• A central issue will be one of functional correspondence: Does Google's "Watch Unlock" system, which uses proximity detection for user convenience, perform the specific cryptographic operations recited in the claims-such as transmitting "time variable secure key information" under the control of a "certification authority"-or is there a fundamental mismatch in the technical purpose and operation between the accused feature and the patented invention?
• A key question of claim scope will be whether terms like "key generating component" require integration into a formal Public Key Infrastructure as consistently described in the patent specifications, or if they can be construed more broadly to cover any wearable device that transmits a signal to unlock a paired phone.
• An evidentiary challenge for the plaintiff will be to prove the technical mechanism of the accused Google features. The case may hinge on whether discovery reveals that the Pixel Watch and phone exchange "time variable" cryptographic keys in a manner that maps onto the patent claims, as opposed to using a static pairing key and simple Bluetooth-based presence detection.