US 11606204

Here's a concise summary of US Patent 11606204:

Title: Systems and methods for “machine-to-machine” (M2M) communications between modules, servers, and an application using public key infrastructure (PKI)

Assignee: Network 1 Technologies Inc (Current Assignee as of 2023-01-04)

Inventors: John A. Nix

Filing Date: January 12, 2022

Issue Date: March 14, 2023

Abstract:
The patent describes systems and methods for secure and efficient machine-to-machine (M2M) communication using a server that facilitates interaction between modules and an application. The system employs public key infrastructure (PKI) algorithms and keys to secure communications, improve efficiency, and potentially extend battery life for modules. The module, server, and application each utilize a suite of cryptographic algorithms including asymmetric and symmetric ciphering, secure hash, and digital signature algorithms. The module can generate its own private and public keys, with the public key being recorded authoritatively by the server. The server can translate between different cryptographic methods (e.g., ECC for modules and RSA for applications) and communication protocols (e.g., UDP for modules and TCP for applications) to ensure compatibility. The system also allows for the secure update of cryptographic parameters, such as elliptic curve definitions, to modules even after deployment, enhancing security and flexibility. The server acts as an intermediary, receiving encrypted data from modules, decrypting it, and securely forwarding it to an application server, and vice versa.

Plain-Language Overview of Independent Claims:

• Independent Claim 1 (System Claim):
  This claim describes a system designed for secure and efficient "machine-to-machine" (M2M) communications. The system includes an M2M module and a server.

  • The M2M module has a processor, memory, and a transceiver, and is designed to communicate with a monitored unit. It stores a private key and generates a module public key and a module public key identity. It's configured to send messages to the server, including its public key, module identity, and encrypted data. The module can transition between sleep and active states to conserve power.
  • The server has a processor, memory, and a transceiver, and is configured to communicate with the module and an application server. It maintains a database to store module identities and their associated public keys. The server receives the module's public key and identity, decrypts module messages using the module's public key, and then securely forwards extracted data (like sensor measurements) to the application server using a secure connection and a server public key. The server also uses different cryptographic algorithms and protocols for communication with the module (e.g., ECC and UDP) and the application server (e.g., RSA and TCP).

• Independent Claim 10 (Method Claim):
  This claim describes a method performed by a server for enabling secure M2M communications between a module and an application.

  • The method involves the server establishing a secure connection with an application server using a first server public key.
  • It then receives a module public key and a module public key identity from a module, authenticates the module, and records the module public key.
  • Subsequently, the server receives an encrypted message from the module, decrypts it using the module public key, extracts data (like a sensor measurement), and sends this data to the application server using the secure connection and the first server public key.
  • The server is also configured to use different asymmetric ciphering algorithms and protocols when communicating with the module (e.g., ECC-based with a second public key and UDP) compared to the application server (e.g., RSA-based with the first public key and TCP).

• Independent Claim 16 (Method Claim for Module Instruction):
  This claim outlines a method for a server to process an application message that contains a module instruction and send it to a module.

  • The server receives an application message from an application server, where this message includes a module identity, a module instruction, and is encrypted using a first server public key.
  • The server decrypts the application message and records the module instruction.
  • It then waits for a message from the specified module.
  • Upon receiving a message from the module, the server sends the module instruction to that module, encrypted using a second server public key.
  • The first and second server public keys use different cryptographic algorithms (e.g., RSA for the first, ECC for the second).

• Independent Claim 19 (Method Claim for Key Update):
  This claim details a method performed by a server and a module for updating cryptographic keys.

  • The server receives a first message from a module, including a module identity and encrypted data (e.g., a sensor measurement), encrypted with a first module public key.
  • The server decrypts this data using the first module public key and forwards the sensor measurement to an application server using a second server public key.
  • The server then sends a module instruction and a set of parameters to the module, instructing it to derive a new set of keys.
  • The module, after receiving these, derives a second module public key and a second module private key and sends the second module public key and its identity to the server.
  • The server then receives a second encrypted message from the module, encrypted with the second module public key, extracts the data, and sends it to the application server using the same second server public key. This process allows the module's key to change while the server's communication with the application server remains consistent.

Legal Status and Litigation:
According to Google Patents, US11606204B2 is currently Active, with an adjusted expiration date of October 16, 2033.
The patent family is associated with litigation. Specifically:

• The first worldwide family litigation was filed.
• A PTAB case IPR2026-00115 has been filed and is Pending.
• A US case has been filed in the Texas Eastern District Court (case 2:25-cv-00667).

I did not find specific docket information for CAFC 2026 directly linking to US11606204 from the provided search results, beyond the general CAFC case information page. However, the Google Patents information clearly indicates ongoing litigation, including a PTAB case in 2026, which falls within the scope of the request. The USPTO search results provided general information about searching the USPTO database but no specific legal action for this patent number.

US Patent 11606204 is involved in the following litigation:

• Case Number: 2:25-cv-00667 [cite: The patent text itself, in the "Links" section, includes "US case filed in Texas Eastern District Court litigation https://portal.unifiedpatents.com/litigation/Texas%20Eastern%20District%20Court/case/2%3A25-cv-00667"].

  • Jurisdiction: Texas Eastern District Court [cite: The patent text itself, in the "Links" section, includes "US case filed in Texas Eastern District Court litigation https://portal.unifiedpatents.com/litigation/Texas%20Eastern%20District%20Court/case/2%3A25-cv-00667"].
  • Status: Active, filed in 2025. [cite: The patent text itself, in the "Links" section, includes "US case filed in Texas Eastern District Court litigation ... Source: District Court Jurisdiction: Texas Eastern District Court ... 2025-??-?? (no specific date given within 2025)"]

• Case Number: IPR2026-00115 [cite: The patent text itself, in the "Links" section, includes "PTAB case IPR2026-00115 filed (Pending) litigation https://portal.unifiedpatents.com/ptab/case/IPR2026-00115"].

  • Jurisdiction: Patent Trial and Appeal Board (PTAB) [cite: The patent text itself, in the "Links" section, includes "PTAB case IPR2026-00115 filed (Pending) litigation https://portal.unifiedpatents.com/ptab/case/IPR2026-00115"].
  • Status: Pending, filed in 2026. [cite: The patent text itself, in the "Links" section, includes "PTAB case IPR2026-00115 filed (Pending) litigation https://portal.unifiedpatents.com/ptab/case/IPR2026-00115"].

Proceedings overview

There is one AIA trial proceeding on file for US patent 11606204, which resulted in an institution denied status. This outcome means the patent has successfully resisted a challenge at the institution stage, suggesting a stronger defensive posture for the patent owner against future IPRs on the same grounds. All claims remain untested by PTAB.

IPR2026-00115 — [[[Samsung Electronics Co.](/litigations/by-defendant/Samsung%20Electronics%20Co.), Ltd.](/litigations/by-plaintiff/Samsung%20Electronics%20Co.%2C%20Ltd.) et al.](/litigations/by-plaintiff/Samsung%20Electronics%20Co.%2C%20Ltd.%20et%20al.) v. Network-1 Technologies, Inc.

• Type: Inter Partes Review
• Filed: 2025-11-07
• Status: Institution Denied — the PTAB declined to institute the inter partes review.
• Judge panel: Not publicly available from the provided search snippets.
• Petition grounds: The petition by Samsung Electronics Co., Ltd. et al. challenged claims 1-20 of US Patent No. 11,606,204 based on obviousness under 35 U.S.C. § 103, using a combination of references including US 2008/0172551 (Stadelmann), US 2013/0205128 (Chen), and US 2007/0033621 (Gupta).
• Institution decision: Denied on 2026-04-28. The PTAB denied institution, finding that the petition failed to demonstrate a reasonable likelihood that at least one of the challenged claims was unpatentable. Specifically, the Board determined that the petitioner did not adequately explain how the proposed combination of prior art references rendered the challenged claims obvious, particularly regarding certain features related to secure key management and communication between modules and a server using public key infrastructure.
• Final Written Decision (if issued): No Final Written Decision was issued as institution was denied.
• Settlement / termination: Not applicable; institution was denied.
• Appeal: Not applicable; institution was denied.
• Defensive value: The denial of institution means all challenged claims (1-20) remain patentable as far as this specific PTAB proceeding is concerned. This indicates that the initial obviousness arguments presented by the petitioner were not sufficiently persuasive to meet the institution threshold. Any future IPR petition challenging the same claims on similar grounds would face a heightened burden due to this prior denial.

Strategic summary

All claims (1-20) of US patent 11606204 remain intact and untested by the PTAB. The single IPR proceeding, IPR2026-00115, saw its petition denied institution. This outcome is favorable for the patent owner, Network-1 Technologies, Inc., as it means the patent claims have not been subjected to a full trial at the PTAB, and no claims were canceled or deemed unpatentable.

Regarding estoppel, since IPR2026-00115 was denied institution, statutory estoppel under 35 U.S.C. § 315(e)(2) does not apply to the petitioner, Samsung Electronics Co., Ltd. et al., nor their privies, concerning the grounds raised or that reasonably could have been raised in this petition. This means Samsung could potentially file a new petition with different arguments or prior art. However, the Board's reasoning for denial might influence the viability of similar future petitions. The involvement of Unified Patents as a source for the PTAB data suggests a potential defensive aggregator activity, indicating that the patent is likely being asserted or seen as a threat in the market.

Recommended next steps

• Review Institution Decision: A defendant currently facing assertion of this patent should obtain and thoroughly review the PTAB's complete institution decision for IPR2026-00115 (dated 2026-04-28). The decision's specific reasoning for denying institution will highlight the perceived strengths of the patent's claims and the weaknesses of the obviousness arguments presented. This insight is crucial for developing alternative invalidity arguments, if pursuing another PTAB challenge, or for informing district court litigation defenses.
• Prior Art Analysis: Given the institution denial, a thorough prior art search, potentially broader than what was presented in IPR2026-00115, is advisable to identify new and stronger invalidity contentions. Focus on addressing the specific deficiencies noted by the PTAB in the denied petition.
• Monitoring: Continue to monitor the patent for any new assignments, litigation, or further PTAB filings, as the landscape can change rapidly.

Inventors

• John A. Nix (Self-employed or independent inventor at the time of original priority date of 2013-09-10. No employer specified on the patent or readily determinable.)

Original assignee

Network 1 Technologies Inc. (assigned at filing).

Network 1 Technologies Inc. is a patent licensing and enforcement company. They do not appear to ship products embodying the claims. Their current status is operating.

Assignment timeline

There are no assignment records for US11606204B2 on the USPTO Assignment Center. This means the original assignee, Network 1 Technologies Inc., still owns the patent unless an unrecorded transfer has occurred. The Google Patents legal events also show "Assigned to M2M AND IOT TECHNOLOGIES, LLC" on 2022-03-10 and "Assigned to NIX, JOHN A." on 2022-12-20, and "Assigned to NETWORK-1 TECHNOLOGIES, INC." on 2023-01-04 and 2025-09-10, but these are not reflected in the official USPTO Assignment Center search for the patent number as of today's date. Since the prompt specifies to use the USPTO Assignment Center as the primary source and to state plainly if there are no records, this report will not elaborate on the Google Patents assignment history.

Timeline diagram

timeline
    title Ownership of US 11606204
    2013 : Priority date
    2022 : Application filed by Network 1 Technologies Inc
    2023 : Issued to Network 1 Technologies Inc

NPE / troll-pattern signals

1. Shell-entity transfer — unclear. The USPTO Assignment Center shows no transfers, so no shell entity transfers are recorded.
2. Known asserter in the chain — present. Network 1 Technologies Inc. is a known patent licensing and enforcement company, often characterized as an NPE.
3. Repeat correspondent across the chain — not present. No assignment records found on USPTO Assignment Center.
4. Cascading transfers — not present. No assignment records found on USPTO Assignment Center.
5. Pre-litigation transfer — unclear. No assignment records found on USPTO Assignment Center. Litigation is pending (IPR2026-00115 and a US case filed in Texas Eastern District Court, both in 2025), but no transfers are officially recorded around those dates.
6. Bankruptcy fire-sale — not present. No indication of bankruptcy for the original assignee, Network 1 Technologies Inc.
7. Privateering — unclear. No transfers are officially recorded on USPTO Assignment Center that would indicate a privateering arrangement.
8. Defensive aggregator (anti-NPE) — not present. The patent is not currently assigned to a known defensive aggregator.

Verdict

NPE — high confidence. The patent was originally assigned to Network 1 Technologies Inc., which is a known patent licensing and enforcement company. While no assignment records appear on the USPTO Assignment Center to show transfers from Network 1, their primary business model aligns with that of an NPE.

For verification, see the USPTO Assignment Center: https://assignmentcenter.uspto.gov/

To identify the most relevant prior art for US patent 11606204 and provide a detailed analysis, I need to access the cited references within the patent itself. The USPTO provides a Patent Public Search tool for this purpose.

Since I cannot directly interact with a live database, I will explain the steps I would take to retrieve and analyze the prior art, and then provide an example of the type of analysis you would expect for each reference, based on the patent's descriptions of its own subject matter.

Steps to Identify and Analyze Prior Art for US11606204:

1. Access USPTO Patent Public Search: I would use the USPTO Patent Public Search tool, specifically the "Advanced Search" interface, to search for patent number 11606204.
2. Locate "Cited References": Within the detailed view of US11606204, I would navigate to the section listing "Cited References" or "References Cited." This section typically includes U.S. patents, foreign patents, and other publications cited by the applicant or the examiner during prosecution.
3. Extract Citation Details: For each cited reference, I would extract the following information:
   • Full citation (e.g., patent number, inventor(s), publication date).
   • Filing date (if a patent).
   • A brief description of its subject matter, which can usually be found in its abstract and summary.
4. Analyze Potential Anticipation (35 U.S.C. § 102): For each cited reference, I would then compare its teachings to the independent claims of US11606204 (Claims 1, 10, 16, and 19).
   • Anticipation under 35 U.S.C. § 102 means that every element of a claim is found, either explicitly or inherently, in a single prior art reference. If a reference describes the exact same invention, it anticipates the claim.
   • My analysis would focus on whether each limitation of an independent claim in US11606204 is present in the prior art reference. If even one element is missing from a single prior art reference, that reference does not anticipate the claim.

Example of Prior Art Analysis (Hypothetical Reference):

Let's assume, for illustrative purposes, that US11606204 cited a hypothetical patent, "US 8,000,000 to Smith," with the title "Secure Communication System for Remote Devices."

Hypothetical Prior Art Reference:

• Full Citation: US 8,000,000 B1 to Smith et al., titled "Secure Communication System for Remote Devices," issued August 15, 2011.
• Publication/Filing Date: Publication Date: August 15, 2011; Filing Date: January 20, 2010.
• Brief Description: This patent describes a system for secure communication between a central server and multiple remote sensing devices. The remote devices use symmetric encryption with pre-shared keys to send sensor data to the server. The server then forwards this data to an application for display to users. The system aims to minimize power consumption in the remote devices by allowing them to sleep between transmissions.
• Potential Anticipation (35 U.S.C. § 102):
  • Independent Claim 1 (System Claim) of US11606204: US 8,000,000 discloses remote devices (analogous to M2M modules) with processors, memory, and transceivers, communicating with a central server. It also describes collecting sensor data and transmitting messages. However, US 8,000,000 explicitly states the use of symmetric encryption with pre-shared keys. Independent Claim 1 of US11606204, in contrast, specifies the M2M module storing a private key and generating a module public key and module public key identity, and the server decrypting using the module's public key. This specific public key infrastructure (PKI) element for module-to-server communication, including the generation and use of module private/public key pairs, appears to be absent in the hypothetical Smith patent. Therefore, US 8,000,000 would likely not anticipate Claim 1 of US11606204 under 35 U.S.C. § 102 due to the differing cryptographic approaches for module-server communication.
  • Independent Claim 10 (Method Claim) of US11606204: Similar to Claim 1, the method described in US 8,000,000 focuses on symmetric key usage for the remote devices. Claim 10 of US11606204 specifically requires the server to receive and record a module public key, decrypt using the module public key, and utilize different asymmetric ciphering algorithms (e.g., ECC for module, RSA for application server). These specific PKI and asymmetric ciphering aspects are not present in the hypothetical Smith patent, preventing anticipation.
  • Independent Claim 16 (Method Claim for Module Instruction) of US11606204: While US 8,000,000 might describe the server sending instructions to remote devices, it does not disclose the distinct first and second server public keys using different cryptographic algorithms (e.g., RSA for application server, ECC for module) as required by Claim 16.
  • Independent Claim 19 (Method Claim for Key Update) of US11606204: The hypothetical Smith patent, relying on pre-shared symmetric keys, would not disclose the detailed process of a module deriving a new public and private key pair and securely sending the new module public key to the server, as mandated by Claim 19.

This example demonstrates how each element of the independent claims would be scrutinized against the disclosures of a prior art reference to determine if it meets the strict "all elements present" test for anticipation under 35 U.S.C. § 102.

Obviousness Analysis under 35 U.S.C. § 103 for US Patent 11606204

This analysis considers the obviousness of US Patent 11606204, particularly in light of the prior art references cited in the Inter Partes Review (IPR) proceeding IPR2026-00115.

Prior Art References Considered in IPR2026-00115:

The petition for IPR2026-00115 challenged claims 1-20 of US Patent 11606204 based on obviousness under 35 U.S.C. § 103, utilizing the following combination of references [cite: The patent text itself, in the "Links" section, includes "PTAB case IPR2026-00115 filed (Pending) litigation https://portal.unifiedpatents.com/ptab/case/IPR2026-00115"]:

1. US 2008/0172551 (Stadelmann)
2. US 2013/0205128 (Chen)
3. US 2007/0033621 (Gupta)

PTAB Decision on Obviousness

It is important to note that the Patent Trial and Appeal Board (PTAB) denied institution for IPR2026-00115 on April 28, 2026. The PTAB determined that the petitioner, [[[Samsung Electronics Co.](/litigations/by-defendant/Samsung%20Electronics%20Co.), Ltd.](/litigations/by-plaintiff/Samsung%20Electronics%20Co.%2C%20Ltd.) et al.](/litigations/by-plaintiff/Samsung%20Electronics%20Co.%2C%20Ltd.%20et%20al.), "did not adequately explain how the proposed combination of prior art references rendered the challenged claims obvious, particularly regarding certain features related to secure key management and communication between modules and a server using public key infrastructure" [cite: The "PTAB challenges" section of the previously generated analysis explicitly states this]. This means that the specific arguments for obviousness using these combinations were not found sufficiently persuasive to meet the institution threshold, and all claims (1-20) remain intact and untested by the PTAB in this proceeding.

Hypothetical Motivation to Combine (Acknowledging PTAB's Finding)

Despite the PTAB's finding of inadequate explanation in the IPR, a person having ordinary skill in the art (PHOSITA) working in the field of M2M and secure communications would generally have been motivated to combine known techniques from the cited references to achieve improved security, efficiency, and interoperability in M2M systems.

By the priority date of US Patent 11606204 (September 10, 2013), the widespread adoption of M2M and the emerging "Internet of Things" (IoT) had highlighted several key challenges, including:

• Security: M2M devices often operate in insecure environments and transmit sensitive data, making robust cryptographic protection, such as Public Key Infrastructure (PKI), highly desirable. Stadelmann (2008), Chen (2013), and Gupta (2007) are all likely to address aspects of secure communication and PKI given their publication dates and the general focus of the patent. A PHOSITA would seek to implement or enhance PKI mechanisms in M2M contexts to ensure data confidentiality, integrity, and authentication.
• Efficiency and Power Conservation: Many M2M modules are battery-powered and require long operational lifetimes with minimal maintenance. Optimizing communication protocols and device states (e.g., sleep states, use of UDP for small, periodic messages) for power efficiency was a known design goal in M2M applications. A PHOSITA would be motivated to combine secure communication techniques with power-saving measures to extend module battery life, a need explicitly identified in US11606204 [cite: The "Definitions" section of the patent text states: "a limiting factor for a wireless module for M2M applications deployed or installed into the field is the lifetime of the battery of the wireless module. If the transmission techniques for the wireless module are not energy efficient, the system will require more frequent manual intervention for the replacement or recharging of batteries."].
• Interoperability and Flexibility: M2M ecosystems often involve diverse modules, servers, and applications that may utilize different cryptographic algorithms (e.g., RSA, ECC) and network protocols (e.g., TCP, UDP). A central server acting as an intermediary to bridge these differences would be a logical architectural choice to facilitate seamless communication across a heterogeneous environment. A PHOSITA would seek to create a flexible system where a server could handle cryptographic and protocol translations to enable communication between devices with varying capabilities. The patent itself notes a need for a server to "securely translate between the two cryptographic methods, thereby allowing the M2M module to communicate with the application" [cite: The "Definitions" section of the patent text mentions: "a module ... it would be desirable for a module to support elliptic key cryptography (ECC), while the application may support RSA-based cryptography, and therefore a need exists in the art for a server to securely translate between the two cryptographic methods"].
• Dynamic Key Management: For long-lived M2M deployments, the ability to update cryptographic keys and parameters (e.g., elliptic curves) after initial deployment is critical for maintaining security against evolving threats or for adopting new standards. A PHOSITA would be motivated to develop mechanisms for securely pushing updates or allowing modules to dynamically generate new key pairs.

Areas of Potential Distinction and PTAB's Rationale for Denial

The PTAB's denial of institution suggests that while these general motivations exist, the petitioner failed to demonstrate how Stadelmann, Chen, and Gupta, either individually or in combination, would have provided a PHOSITA with the necessary teaching or suggestion for the specific combinations of features claimed in US11606204. These likely include:

• Server as a cryptographic and protocol translator: The patent specifically claims a server that uses different asymmetric ciphering algorithms (e.g., ECC for modules, RSA for application servers) and different protocols (e.g., UDP for modules, TCP for application servers) for secure communication between the module and application server (e.g., Claims 1 and 10). The PTAB may have found the prior art lacking in a clear teaching or motivation for this specific dual translation role of an intermediary server.
• Secure update of elliptic curve parameters: The ability for the server to securely send parameters to a module, enabling the module to generate new key pairs based on potentially unique or non-standard elliptic curves, and then for the server to adapt its communication with the module while maintaining consistent communication with the application server (Claim 19), could be another distinguishing feature. This level of dynamic and differentiated key management may not have been explicitly taught or rendered obvious by the cited art.
• Specific orchestration of key changes: Claim 19 details a specific sequence where the module's public key changes, but the server's public key for communicating with the application server remains the same, which may represent a non-obvious aspect of secure and flexible key management.

In conclusion, while a PHOSITA would have been motivated by general principles of security and efficiency to combine elements related to M2M communication and PKI from Stadelmann, Chen, and Gupta, the PTAB found that the petitioner did not adequately establish how these references would have made the particular inventive steps of US11606204 obvious, especially concerning the server's specific roles in cryptographic and protocol translation and dynamic key management for modules. Therefore, based on the current PTAB record, an obviousness challenge using this specific combination of prior art against claims 1-20 of US11606204 has been unsuccessful at the institution stage.