Stormborn Tech LLC v. Sierra Wireless America Inc

I. Executive Summary and Procedural Information

• Parties & Counsel:
  • Plaintiff: Stormborn Technologies LLC (Texas)
  • Defendant: Sierra Wireless America, Inc. (Delaware)
  • Plaintiff’s Counsel: Chong Law Firm PA; SAND, SEBOLT & WERNOW CO., LPA
• Case Identification: 1:19-cv-02198, D. Del., 11/25/2019
• Venue Allegations: Venue is alleged to be proper in the District of Delaware because Defendant is incorporated in Delaware, which the complaint asserts makes it a resident of the district for patent venue purposes under the Supreme Court's decision in TC Heartland.
• Core Dispute: Plaintiff alleges that Defendant’s wireless modems and gateways infringe a patent related to dynamically adjusting data transmission rates in a wireless communication system based on signal quality feedback.
• Technical Context: The technology addresses the challenge of maintaining reliable connections in spread-spectrum wireless systems by adaptively trading data speed for signal robustness, a foundational technique for modern cellular and wireless data networks.
• Key Procedural History: The patent-in-suit is a reissue patent, which reissued from U.S. Patent No. 7,613,247. The patent family claims priority back to an application filed in June 2000. Reissue proceedings can introduce prosecution history that may be relevant for claim construction and the doctrine of equivalents.

Case Timeline

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

U.S. Reissue Patent No. RE44,199 - "Variable throughput reduction communications system and method"

• Patent Identification: U.S. Reissue Patent No. RE44,199 (“Variable throughput reduction communications system and method”), issued May 7, 2013.

The Invention Explained

• Problem Addressed: The patent describes a problem in multi-cell wireless systems where a device near the edge of a cell experiences significant interference from adjacent cells, which can degrade the signal and increase the error rate to an unusable level (’199 Patent, col. 1:50-57). Previous methods to combat this, such as increasing the system's processing gain, were inefficient because they required reducing the data rate and changing the fundamental architecture of the receiver (’199 Patent, col. 1:58-66).
• The Patented Solution: The invention discloses a closed-loop feedback system to manage data throughput dynamically. A receiver monitors the error rate of the incoming data signals, and a "command processor" uses this information to generate a "data-rate control signal" (’199 Patent, col. 2:62-66). This control signal is sent back to the original transmitter, instructing it to adjust its transmission rate to maintain a desired signal quality (’199 Patent, col. 3:6-9). The system can, for example, lower the effective data rate by sending the same data over multiple parallel channels to increase signal power and robustness at the receiver, as depicted in the relationship between the transmitter in Figure 4 and the receiver’s feedback loop in Figure 5 (’199 Patent, Fig. 4, Fig. 5).
• Technical Importance: This approach provides a method for what is now commonly known as adaptive modulation and coding, allowing a communication system to automatically sacrifice speed for reliability in challenging radio frequency (RF) environments, a core principle for ensuring stable connections in cellular and Wi-Fi networks (’199 Patent, col. 2:10-19).

Key Claims at a Glance

• The complaint asserts independent claims 11 (a receiver apparatus) and 13 (a method of recovering data) (Compl. ¶¶ 17, 19).
• Independent Claim 11 recites a receiver comprising five key circuitries:
  • "demodulator circuitry" for detecting transmitted signals.
  • "decoder circuitry" for decoding the signals and providing an "error rate".
  • "command processor circuitry" responsive to the "error rate" for generating a "data-rate control signal" to be sent to the transmitter.
  • "transmitting circuitry" for conveying the "error rate dependent rate control signal" back to the transmitter.
  • "multiplexer circuitry" for combining the decoded data into a single stream.
• Independent Claim 13 recites a method with steps that largely mirror the functions of the circuitry in claim 11.
• The complaint reserves the right to assert dependent claims, specifically mentioning claims 12 and 14, which add the limitation of decoding Forward Error Correction (FEC) codes of different rates (Compl. ¶¶ 18, 20, 49).

III. The Accused Instrumentality

Product Identification

• "Sierra Wireless GL Series Modems and FX Series Gateways" (the "Accused Product") (Compl. ¶25).

Functionality and Market Context

• The complaint identifies the Accused Product as a "receiver for recovering wireless data" (Compl. ¶25). The allegations state that the Accused Product, "at least in internal testing and usage," practices the claimed method and contains the claimed circuitry (Compl. ¶¶ 32-38). The complaint does not provide specific details on the operational mechanisms of the Accused Product or its market position, instead alleging in a conclusory manner that its components perform the functions recited in the patent claims (Compl. ¶¶ 26-31).

No probative visual evidence provided in complaint.

IV. Analysis of Infringement Allegations

The complaint’s infringement theory is based on mapping the functions of the Accused Product directly onto the elements of the asserted claims. The complaint references an exemplary claim chart in "Exhibit B" which was not publicly filed with the complaint; the analysis below is based on the narrative allegations (Compl. ¶¶ 25-38).

• RE44,199 Infringement Allegations

• Identified Points of Contention:
  • Scope Questions: Claim 11 is for a "receiver," but it includes limitations directed to a closed-loop system involving a separate transmitter (e.g., generating and transmitting a control signal to the transmitter). A central question may be one of divided infringement: does the complaint provide a basis to hold Defendant responsible for the entire claimed system, including the actions of the transmitter that receives and acts upon the control signal? The complaint's focus on the "Accused Product" as a receiver may create a challenge in proving infringement of the complete system claim.
  • Technical Questions: The complaint alleges the Accused Product has "command processor circuitry" that performs the claimed function (Compl. ¶28). A key technical question for the court will be whether the processing in Defendant's modems is "responsive to the error rate" for the specific purpose of "generating a data-rate control signal" to be sent back to the transmitter, as required by the claim. The defense may argue that any processing is for other standard functions (e.g., local error correction, network reporting) and does not meet the specific functional requirements of this claim limitation.

V. Key Claim Terms for Construction

• The Term: "command processor circuitry responsive to the error rate ... for generating a data-rate control signal"

• Context and Importance: This term is the functional heart of the invention, defining the "brain" of the adaptive feedback loop. The outcome of the case may depend on whether the processing performed by the accused devices falls within the scope of this term.

• Intrinsic Evidence for Interpretation:

  • Evidence for a Broader Interpretation: The patent describes the processor's function broadly as determining "a desired-data rate" and generating a corresponding "data-rate command signal" (’199 Patent, col. 4:62-66). A plaintiff may argue this language supports a construction covering any processor that performs this general feedback function, irrespective of the specific algorithm or implementation.
  • Evidence for a Narrower Interpretation: The specification also describes the command processor generating an "adder-control signal" and a "multiplexer signal" in addition to the data-rate command (’199 Patent, col. 7:51-55). A defendant may argue that these more specific functions described in the preferred embodiment should inform a narrower construction of the processor's required operations.

• The Term: "data rate control signal controlling operation of circuitry at the transmitter"

• Context and Importance: This limitation defines the purpose and effect of the signal generated by the claimed receiver. Proving infringement requires showing not just the generation of a signal, but one that has this specific controlling effect on a transmitter.

• Intrinsic Evidence for Interpretation:

  • Evidence for a Broader Interpretation: The claim language is functional ("controlling operation"). A plaintiff may argue that any signal that results in the transmitter changing its data rate in response to the receiver's feedback meets this limitation.
  • Evidence for a Narrower Interpretation: The specification describes a specific implementation where the control signal "controls into how many data channels the demultiplexer demultiplexes the input data" at the transmitter (’199 Patent, col. 3:8-11; Fig. 4). A defendant might argue that the term should be limited to this specific mechanism of control, rather than covering any method of rate adjustment.

VI. Other Allegations

• Indirect Infringement: The complaint includes a count for induced infringement, alleging that Defendant encouraged others to infringe and knew that such acts constituted infringement (Compl. ¶44). The complaint does not, however, plead specific facts to support this, such as references to user manuals, marketing materials, or technical documentation that allegedly instruct users on how to perform the infringing method.
• Willful Infringement: The complaint alleges that Defendant "has had knowledge of infringement of the ’199 Patent at least as of the service of the present Complaint" (Compl. ¶42). This allegation appears to support a claim for post-filing willfulness only, as no facts suggesting pre-suit knowledge of the patent or infringement are alleged.

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

• A core issue will be one of system scope: Can the Plaintiff prove that the Defendant, by making and selling receivers, is liable for infringing claims that recite a complete, two-way communication system, including a transmitter that must receive and act upon a control signal? The case may turn on whether the infringement allegations can overcome potential divided infringement issues.
• A key evidentiary question will be one of functional proof: What technical evidence will be offered to show that the processors in the accused modems perform the specific function of generating a "data-rate control signal" in response to a measured error rate for the purpose of controlling a remote transmitter, as opposed to performing other, more general network management or signal processing functions? The sparseness of technical detail in the complaint suggests this will be a central point of discovery and dispute.