US 7593428

Patent Analysis: U.S. Patent 7,593,428

Washington, D.C. - April 26, 2026 - An analysis of United States Patent 7,593,428 reveals a method for enhancing data integrity in packet-based communications. The patent, assigned to IOT Innovations LLC, details a system for applying multiple, dynamically selected checksums to different parts of a single data packet.

There is no record of U.S. Patent 7,593,428 in the 2026 dockets of the U.S. Court of Appeals for the Federal Circuit.

Summary of U.S. Patent 7,593,428

Plain-Language Overview of Independent Claims

U.S. Patent 7,593,428 contains four independent claims: 1, 12, 14, and 18. Below is a plain-language explanation of each.

Independent Claim 1: This claim describes a physical apparatus designed to create a specially formatted data packet. The key components are a "formatter" that assembles the data packet and a "selector" that decides which parts of the packet get special error-checking protection (a checksum). A crucial aspect of this invention is that the selector's decisions are influenced by the current conditions of the communication channel, such as how noisy or clear the connection is. In simple terms, it's a device that can adjust the level of error protection for different pieces of data within a single packet based on the quality of the network connection.

Independent Claim 12: This claim focuses on the receiving end of the communication. It outlines an apparatus that takes in a specific type of data packet, known as a User Datagram Protocol lite (UDP-lite) packet. This device has a "checksum extractor" that reads information from the packet's header to understand how different parts of the data were protected against errors. It then uses a "checksum calculator" to perform its own calculations to see if any of the data was corrupted during transmission. Essentially, this is a device that can understand and verify the complex, multi-part error-checking scheme set up by the sending apparatus described in claim 1.

Independent Claim 14: This claim shifts from a physical device to a method or a process. It describes the steps for creating the multi-checksum data packet. The process involves:

1. Receiving data at a transceiver station.
2. Using a processor with programmed instructions to select different portions of the data that need to be protected by different checksums.
3. Performing the necessary checksum calculations for each selected portion.
4. Formatting the data into a packet that includes the data portions and the corresponding checksum information.

This claim essentially covers the software or firmware instructions that would make the apparatus in claim 1 function.

Independent Claim 18: This claim details the method used by the receiving device. The steps are:

1. Receiving a UDP-lite data packet at a transceiver.
2. Using a processor with programmed instructions to extract the different checksum values from the packet's header, each associated with a different data portion.
3. Performing checksum calculations on each data portion based on the extracted information.
4. Verifying the integrity of each data portion by comparing the calculated checksum with the one sent in the packet.

Similar to claim 14, this claim represents the operational method for the apparatus described in claim 12.

Litigation History of U.S. Patent 7,593,428

U.S. Patent 7,593,428, currently assigned to IOT Innovations LLC, has been asserted in numerous patent infringement lawsuits. The plaintiff in all known cases is IOT Innovations LLC.

Below is a list of known litigation involving this patent. All cases are currently open unless otherwise specified.

A notable ruling occurred in the case against SimpliSafe, Inc. (1:23-cv-10352). On June 28, 2023, the court denied SimpliSafe's motion to dismiss the case, allowing the claims for direct infringement, indirect infringement, and willful infringement to proceed. The court affirmed that the plaintiff, IOT Innovations LLC, had met the necessary pleading standards to continue with the lawsuit.

Proceedings overview

The USPTO Open Data Portal (ODP) API currently indicates no AIA trial proceedings on file for U.S. Patent 7,593,428. A comprehensive web search for Inter Partes Review (IPR), Post-Grant Review (PGR), or Covered Business Method (CBM) proceedings related to this patent also yielded no results, indicating no PTAB activity has been initiated against US7593428. This means all claims of the patent are currently untested by PTAB challenges.

Strategic summary

As of June 1, 2026, all claims of U.S. Patent 7,593,428 remain untested by AIA trial proceedings before the Patent Trial and Appeal Board. There are no canceled, sustained, or partially invalidated claims from PTAB challenges. Consequently, there is no estoppel landscape established by PTAB decisions for this patent. All potential prior-art grounds remain available for a defendant to assert, either in district court litigation or in a future PTAB petition, subject to statutory time bars (e.g., the one-year bar for IPR petitions following service of a complaint alleging infringement).

Recommended next steps

Given the absence of any PTAB activity, a defendant facing assertion of U.S. Patent 7,593,428 would have all options open for challenging patentability before the PTAB, subject to the one-year statutory deadline for filing an IPR petition after being served with a complaint alleging infringement.

Inventors

• Keith Miller (Employer at time of filing: Nokia Corporation - inferred from initial assignment from Nokia)
• Marta Karzewicz (Employer at time of filing: Nokia Corporation - inferred from initial assignment from Nokia)

It is inferred that both inventors were employed by Nokia Corporation at the time of filing, given that Nokia Corporation is the assignor in the first recorded assignment, which transferred the patent from Nokia to Spyder Navigations L.L.C.

Original assignee

The original assignee, as identified by the first assignor in the chain, was Nokia Corporation. Nokia Corporation is a multinational telecommunications, information technology, and consumer electronics company. They historically shipped, and continue to ship, a wide range of products embodying various communication technologies. Nokia Corporation is currently an operating company.

Assignment timeline

• 2011-03-22 (executed) / recorded 2011-03-29 — Reel 026044/0305

  • Conveyance: ASSIGNMENT OF ASSIGNORS INTEREST
  • Assignor: NOKIA CORPORATION
  • Assignee: SPYDER NAVIGATIONS L.L.C., DELAWARE
  • Correspondent: BEYER LAW GROUP LLP, MARK A BORCHARDT, NEW YORK, NY
  • Context: transfer from operating company to a potentially asserting entity

• 2011-07-18 (executed) / recorded 2011-07-22 — Reel 026637/0611

  • Conveyance: MERGER
  • Assignor: SPYDER NAVIGATIONS L.L.C.
  • Assignee: INTELLECTUAL VENTURES I LLC, DELAWARE
  • Correspondent: LERNER, DAVID, LITTENBERG, KRUMHOLZ & MENTLIK, LLP, LARRY M. GOLDSTEIN, WESTFIELD, NJ
  • Context: transfer-to-asserter (Intellectual Ventures is a known NPE)

• 2022-07-21 (executed) / recorded 2022-07-21 — Reel 060585/0188

  • Conveyance: ASSIGNMENT OF ASSIGNORS INTEREST
  • Assignor: INTELLECTUAL VENTURES I LLC
  • Assignee: INTELLECTUAL VENTURES ASSETS 189 LLC, DELAWARE
  • Correspondent: MARSHALL GERSTEIN & BORUN LLP, THOMAS L. PHILIPP, CHICAGO, IL
  • Context: internal reorg within the Intellectual Ventures family

• 2022-07-28 (executed) / recorded 2022-08-02 — Reel 060698/0718

  • Conveyance: ASSIGNMENT OF ASSIGNORS INTEREST
  • Assignor: INTELLECTUAL VENTURES ASSETS 189 LLC
  • Assignee: IOT INNOVATIONS LLC, TEXAS
  • Correspondent: NOBLITT & CALDWELL, LLP, W. RALPH CALDWELL, JR., AUSTIN, TX
  • Context: transfer-to-asserter (IOT Innovations LLC is the current plaintiff)

Timeline diagram

timeline
    title Ownership of US 7593428
    2007 : Filed
    2009 : Issued
    2011 : Assigned to Spyder Navigations LLC
         : Acquired by Intellectual Ventures I LLC
    2022 : Transferred to IV Assets 189 LLC
         : Assigned to IOT Innovations LLC

NPE / troll-pattern signals

1. Shell-entity transfer

   • Present: The chain includes transfers to entities with names indicative of shell companies: Spyder Navigations L.L.C. (Reel 026044/0305, 2011-03-29), Intellectual Ventures I LLC (Reel 026637/0611, 2011-07-18), Intellectual Ventures Assets 189 LLC (Reel 060585/0188, 2022-07-21), and the current assignee IOT Innovations LLC (Reel 060698/0718, 2022-08-02). IOT Innovations LLC is actively litigating this patent as a plaintiff, consistent with an NPE.

2. Known asserter in the chain

   • Present: Intellectual Ventures I LLC is a well-known patent assertion entity, appearing as an assignee on Reel 026637/0611 (executed 2011-07-18). IOT Innovations LLC, the current assignee (Reel 060698/0718, 2022-08-02), is identified as the plaintiff in multiple active infringement lawsuits involving this patent.

3. Repeat correspondent across the chain

   • Not present: While W. Ralph Caldwell, Jr. of Noblitt & Caldwell, LLP (Correspondent on Reel 060698/0718) is known for representing patent assertion entities, no single correspondent or firm appears on multiple assignment records within this specific chain.

4. Cascading transfers

   • Present: Two instances of cascading transfers are observed. First, the transfer from Nokia Corporation to Spyder Navigations L.L.C. (Reel 026044/0305, executed 2011-03-22) was followed by a transfer from Spyder Navigations L.L.C. to Intellectual Ventures I LLC (Reel 026637/0611, executed 2011-07-18) within a period of less than four months. Second, Intellectual Ventures I LLC transferred the patent to Intellectual Ventures Assets 189 LLC (Reel 060585/0188, executed 2022-07-21), which then transferred it to IOT Innovations LLC (Reel 060698/0718, executed 2022-07-28) within a single week.

5. Pre-litigation transfer

   • Present: The final transfer to IOT Innovations LLC was executed on 2022-07-28 and recorded on 2022-08-02 (Reel 060698/0718). The first recorded infringement lawsuit against SimpliSafe, Inc. was filed on February 17, 2023. This falls within approximately 6.5 months of the transfer, indicating a transfer in anticipation of litigation.

6. Bankruptcy fire-sale

   • Not present: There is no evidence in the assignment records or public information suggesting that any assignor in the chain, particularly Nokia Corporation, was undergoing bankruptcy proceedings at the time of transfer.

7. Privateering

   • Unclear: While the patent originated from an operating company (Nokia) and was transferred to a known NPE, there is no direct public evidence (e.g., SEC filings, specific reports) confirming that Nokia is actively orchestrating or funding the assertion by IOT Innovations LLC against its competitors.

8. Defensive aggregator (anti-NPE)

   • Not present: The assignment chain terminates with IOT Innovations LLC, an active plaintiff in patent litigation, not a defensive aggregator.

Verdict

NPE — high confidence

The verdict is high confidence NPE due to multiple strong signals. The patent was transferred from an operating company (Nokia Corporation) to a known patent assertion entity, Intellectual Ventures I LLC (Reel 026637/0611, executed 2011-07-18). There were cascading transfers between Intellectual Ventures entities and finally to IOT Innovations LLC (Reel 060585/0188, executed 2022-07-21 and Reel 060698/0718, executed 2022-07-28). The final transfer to IOT Innovations LLC occurred approximately 6.5 months before the first recorded infringement suit, indicating a pre-litigation transfer to an asserting entity.
USPTO Assignment Center Search for US7593428

Analysis of Prior Art for U.S. Patent 7,593,428

This analysis details the prior art cited during the examination of U.S. Patent 7,593,428. Each reference is evaluated for its potential to anticipate the patent's claims under 35 U.S.C. § 102. The core innovation of patent 7,593,428 is the creation and processing of a single data packet containing multiple, distinct, and dynamically selectable portions, each protected by its own checksum, with the selection criteria being responsive to communication channel conditions.

1. U.S. Patent 6,289,023 B1

• Full Citation: Hardware checksum assist for network protocol stacks, issued to Hewlett-Packard Company on September 11, 2001.
• Filing Date: September 25, 1997.
• Brief Description: This patent describes a hardware-based method to offload checksum calculations from the main CPU. It focuses on efficiently calculating a single checksum for a data packet by processing data "on the fly" as it moves between memory and a network interface controller.
• Potential Anticipation: This reference does not anticipate the claims of 7,593,428. Its primary concern is the efficiency of calculating a single checksum for a packet. It does not disclose or suggest using multiple checksums for different, selectable portions within a single packet, nor does it mention dynamically adjusting checksum strategies based on channel conditions.

2. U.S. Patent Application 2002/0184598 A1

• Full Citation: Providing a header checksum for packet data communications, published on December 5, 2002.
• Publication Date: December 5, 2002.
• Brief Description: This application details a method for calculating a checksum for the header of a data packet separately from the payload. This is a common practice in protocols like IP, where the header checksum protects header information, and a higher-layer protocol (like TCP/UDP) handles the payload checksum.
• Potential Anticipation: This reference is unlikely to anticipate the claims. While it involves two checksums in a broad sense (one for the header, one for the payload), it does not teach the novel concept of partitioning the payload or other parts of the packet into multiple, selectable portions, each with its own distinct checksum field in the header. The separation of header and payload checksums is standard and does not reflect the granular, dynamic, multi-part protection claimed in 7,593,428.

3. U.S. Patent 6,954,893 B2

• Full Citation: Method and apparatus for reliable unidirectional communication in a data network, issued to Lockheed Martin Corporation on October 11, 2005.
• Filing Date: August 15, 2000.
• Brief Description: This patent addresses reliable data transfer over unidirectional links (where no acknowledgments can be received). It proposes encapsulating data packets into a "super-packet" or frame that includes forward error correction (FEC) data. This FEC data allows the receiver to reconstruct lost packets.
• Potential Anticipation: This reference does not anticipate the key claims. Its focus is on reliability through FEC and packet bundling, which is a different mechanism from the multiple, distinct checksums within a single packet as claimed in 7,593,428. It does not disclose partitioning a packet into multiple checksum-protected regions.

4. U.S. Patent 7,161,960 B2

• Full Citation: Apparatus, and associated method, for forming, and operating upon, multiple-checksum-protected data packet, issued to Nokia Corporation on January 9, 2007.
• Filing Date: March 26, 2002.
• Brief Description: This patent is the direct parent of 7,593,428, which is a continuation of this application. It describes the same core invention: a method to create and process a data packet with multiple checksum-protected parts, where the protection scheme can be selected dynamically.
• Potential Anticipation: As the parent application, this patent does not act as prior art to invalidate 7,593,428 under 35 U.S.C. § 102. The '960 patent establishes the priority date for the shared invention. The claims of the '428 patent are presumably different in scope but rely on the same disclosure.

5. U.S. Patent 7,269,186 B2

• Full Citation: Protocol for framing a payload, issued to Qualcomm Incorporated on September 11, 2007.
• Filing Date: August 6, 2001.
• Brief Description: This patent discloses a framing protocol where a payload is segmented into one or more frames. Each frame includes a header and a portion of the payload. The header can contain information about the frame, such as its length and sequence number. The protocol is designed for radio link layers.
• Potential Anticipation: This reference does not appear to anticipate the claims. While it deals with segmenting a payload into frames, it does not teach that these frames are part of a single, cohesive data packet at the UDP layer that contains multiple checksum fields in its header for each of these distinct portions. The concept of dynamically selecting these portions based on channel conditions is also absent.

6. U.S. Patent 7,386,627 B1

• Full Citation: Methods and apparatus for precomputing checksums for streaming media, issued to Network Appliance, Inc. on June 10, 2008.
• Filing Date: January 29, 2002.
• Brief Description: This patent describes a system for improving the efficiency of streaming media. It involves pre-calculating checksums for data blocks before they are requested by a client and storing them. When a client requests a specific byte range, the system can quickly construct a packet and its corresponding checksum from the pre-calculated values.
• Potential Anticipation: This reference does not anticipate the claims of 7,593,428. Its innovation lies in the pre-computation and storage of checksums for efficiency, not in the structure of the packet itself. It does not disclose a packet format that contains multiple, selectable checksums for different portions of its own payload.

Conclusion:

The prior art cited by the examiner during the prosecution of U.S. Patent 7,593,428 does not appear to anticipate the independent claims. The references generally relate to checksum calculation efficiency, standard header/payload checksum separation, or framing protocols for reliability, but none disclose the core inventive concept: a single packet structure with multiple, selectable, checksum-protected portions, where the selection can be dynamically altered based on communication conditions. This novel combination of features allows the claims of 7,593,428 to be distinguished from the cited art.

The prior art analysis for U.S. Patent 7,593,428 indicates that none of the cited references individually anticipate the independent claims. However, an analysis under 35 U.S.C. § 103 requires evaluating whether combinations of these references, driven by a motivation that would have been obvious to a person having ordinary skill in the art (PHOSITA), would render the claimed invention obvious.

The core inventive concept of US7593428 is the creation and processing of a single data packet containing multiple, distinct, and dynamically selectable portions, each protected by its own checksum, with the selection criteria being responsive to communication channel conditions and/or data content type. This extends the functionality of protocols like UDP-Lite, which traditionally only offer a binary choice of protecting an entire payload or none of it.

Obviousness Analysis under 35 U.S.C. § 103

A PHOSITA in the field of packet communication systems, particularly those involved with real-time data transmission over variable communication channels (such as radio environments), would have been motivated to enhance the flexibility and robustness of error detection beyond the limitations of standard UDP or UDP-Lite. The patent's background itself identifies the problem that "Conventional UDP checksum protection provides protection for an entire payload portion of a UDP-formatted data packet or for none of the payload portion of the data packet" and that "errors contained in the unprotected part of the data packet do not cause the data packet to be discarded," which can be problematic for applications. The patent explicitly states the need for improved communications if "a second checksum were provided for the data packet" for an "additional portion of the UDP-Lite data packet." This forms a clear motivation for a PHOSITA to seek solutions for more granular and adaptive error protection.

Combination of Prior Art References:
The claims of US7593428 would likely have been obvious to a PHOSITA by combining the teachings of:

1. U.S. Patent Application 2002/0184598 A1 (Bace): Providing a header checksum for packet data communications.
2. U.S. Patent 7,269,186 B2 (Qualcomm): Protocol for framing a payload.
3. General knowledge in the art regarding dynamic adaptation of communication parameters in response to channel conditions.

Motivation for Combination:

1. Motivation to provide multiple checksums for different portions of data:

   • Bace (US20020184598A1) teaches the concept of applying separate checksums to logically distinct sections of a data packet, specifically a header checksum and a payload checksum. A PHOSITA, seeking to overcome the inflexibility of UDP-Lite's single protected/unprotected payload scheme, would be motivated to extend this concept. Instead of merely a header and a single payload checksum, it would be an obvious step to apply the same principle to multiple sub-portions within the payload itself, thereby allowing finer-grained error detection for different data priorities or sensitivities. This directly addresses the stated problem in US7593428 that a single checksum is insufficient.

2. Motivation to define and delineate these multiple portions within a data packet:

   • Qualcomm (US7269186B2) discloses a framing protocol that segments a payload into one or more frames, with each frame including a header that contains information like its length. A PHOSITA would readily recognize that such a well-known payload segmentation technique could be adapted to define the "multiple portions" within a UDP-Lite payload that are intended to be separately checksum-protected. The "length sub-fields" (104) described in US7593428 and referenced in claims 5 and 9 directly correspond to the length indication found in framing protocols like Qualcomm's.

3. Motivation for dynamic selection based on communication conditions or content type:

   • The background of US7593428 notes the relevance of UDP-Lite for "communications in a radio environment." In such environments, communication channel conditions (e.g., signal-to-noise ratio, interference levels) are inherently dynamic and often unpredictable. It is a fundamental and well-established engineering practice in wireless communication systems to dynamically adapt transmission parameters (such as coding rates, modulation schemes, power control, or retransmission strategies) in response to real-time measurements of channel conditions. A PHOSITA, having conceived of applying granular checksum protection to different parts of a packet (through the combination of Bace and Qualcomm), would be strongly motivated to dynamically adjust which parts are protected, and potentially how they are protected (e.g., selecting different checksum types or covering more extensive portions), based on the prevailing communication conditions or the inherent criticality of the data (content type). This dynamic adaptation would optimize resource utilization by providing appropriate levels of error protection only where and when needed, a standard objective in communication system design. The patent itself highlights this, stating, "Dynamic reselection of the characteristics of the data packet is made, for instance, responsive to measurements of communication conditions upon a communication channel... And, such dynamic reselection of the characteristics of the data is also, or alternately, made responsive to the type of data."

Conclusion:
A PHOSITA, motivated by the recognized limitations of existing UDP-Lite checksumming and the desire for more flexible and robust error handling in dynamic communication environments, would have found it obvious to combine the concept of multiple checksums for distinct logical data units (Bace), with a method for defining and delineating these units within a payload (Qualcomm), and to further integrate the well-known practice of dynamically adapting communication parameters based on channel conditions or data type. This combination would lead directly to the apparatus and methods claimed in US7593428 for forming and operating upon a data packet with multiple, dynamically-selected, checksum-protected parts.