Cedar Lane Tech Inc v. Sigma Defense Systems LLC

I. Executive Summary and Procedural Information

• Parties & Counsel:
  • Plaintiff: Cedar Lane Technologies Inc. (Canada)
  • Defendant: Sigma Defense Systems LLC (Delaware)
  • Plaintiff’s Counsel: Rabicoff Law LLC
• Case Identification: 1:22-cv-02884, D. Colo., 11/03/2022
• Venue Allegations: Venue is asserted based on Defendant maintaining an established place of business in the District of Colorado and having allegedly committed acts of infringement within the district.
• Core Dispute: Plaintiff alleges that Defendant infringes two related patents concerning an interface architecture for managing the transfer of data from an image sensor to a processor system.
• Technical Context: The technology addresses the common engineering problem of decoupling a continuously-streaming image sensor from an asynchronous, general-purpose processor by using a memory buffer and an interrupt-based signaling system.
• Key Procedural History: U.S. Patent No. 8,537,242 is a divisional of the application that issued as U.S. Patent No. 6,972,790. This indicates they share a common specification, which may suggest that claim terms should be construed consistently between them. The complaint does not mention any other prior litigation or administrative proceedings.

Case Timeline

Date	Event
2000-01-21	Priority Date (’790 & ’242 Patents)
2000-12-21	’790 Patent Application Filing Date
2005-10-27	’242 Patent Application Filing Date
2005-12-06	’790 Patent Issue Date
2013-09-17	’242 Patent Issue Date
2022-11-03	Complaint Filing Date

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

U.S. Patent No. 6,972,790 - “Host interface for imaging arrays,” issued Dec. 6, 2005

The Invention Explained

• Problem Addressed: The patent’s background section describes a fundamental incompatibility between the continuous, high-speed, synchronized data stream produced by an image sensor and the asynchronous, on-demand data access model of a commercial microprocessor. Bridging this gap traditionally required "additional glue logic," which increased system cost and complexity and undermined the benefits of integrating the sensor and processor on a single chip (’790 Patent, col. 1:38-57).
• The Patented Solution: The invention proposes an integrated interface that acts as a buffer between the image sensor and the processor system. This interface uses a dedicated memory (such as a first-in first-out, or FIFO, buffer) to receive and store image data at the sensor's clock rate. The interface then generates a signal, such as an interrupt, to the main processor once a certain quantity of data has accumulated, allowing the processor to read out the buffered data at its own pace. (’790 Patent, Abstract; col. 2:4-14). This architecture, depicted in system-level diagrams like Figure 1, effectively decouples the timing of the sensor from the timing of the processor.
• Technical Importance: This design facilitates the creation of more integrated and cost-effective "system on a chip" digital imaging devices by eliminating the need for external interface components. (’790 Patent, col. 1:60-67).

Key Claims at a Glance

• The complaint asserts exemplary claims without specifying numbers, but Independent Claim 1 is representative of an apparatus claim.
• Independent Claim 1 requires:
  • a memory for storing imaging array data and clocking signals at a rate determined by the clocking signals;
  • a signal generator for generating a signal for transmission to the processor system in response to the quantity of data in the memory; and
  • a circuit for controlling the transfer of the data from the memory at a rate determined by the processor system.
• The complaint reserves the right to assert additional claims, including dependent claims (Compl. ¶12).

U.S. Patent No. 8,537,242 - “Host interface for imaging arrays,” issued Sep. 17, 2013

The Invention Explained

• Problem Addressed: As a divisional of the ’790 Patent, the ’242 Patent addresses the same technical problem of bridging the timing mismatch between a streaming image sensor and a host processor system (’242 Patent, col. 1:39-58).
• The Patented Solution: The patent describes the same solution but claims it as a method. The method involves receiving image data into a FIFO memory, using a counter to track the amount of stored data, comparing this count to a predefined limit, and then generating an interrupt signal to the processor to trigger the data transfer when the limit is reached. (’242 Patent, col. 5:11-24; Claim 1).
• Technical Importance: The method provides a systematic process for managing data flow in an integrated imaging system, enabling efficient multitasking by the host processor. (’242 Patent, col. 5:15-20).

Key Claims at a Glance

• The complaint asserts exemplary claims without specifying numbers, but Independent Claim 1 is representative of a method claim.
• Independent Claim 1 requires the steps of:
  • receiving image data from an imaging array;
  • storing the image data in a FIFO memory;
  • updating a FIFO counter to maintain a count of the image data;
  • comparing the count of the FIFO counter with a FIFO limit;
  • generating an interrupt signal to a processor based on the comparison and an enable signal; and
  • transferring the image data from the FIFO memory to the processor in response to the interrupt signal.
• The complaint reserves the right to assert additional claims (Compl. ¶21).

III. The Accused Instrumentality

Product Identification

The complaint does not identify any specific accused products by name. It refers to "Exemplary Defendant Products" and states that they are identified in claim charts provided as Exhibit 3 and Exhibit 4 (Compl. ¶12, ¶17, ¶21, ¶26). These exhibits were not filed with the public complaint.

Functionality and Market Context

The complaint does not provide sufficient detail for analysis of the accused products' specific functionality or market context. The allegations are conclusory, stating that the products "practice the technology claimed" by the patents-in-suit (Compl. ¶17, ¶26).

IV. Analysis of Infringement Allegations

The complaint alleges that Defendant's products infringe the patents-in-suit but incorporates the detailed infringement analysis by reference to external exhibits (Exhibits 3 and 4), which are not publicly available (Compl. ¶18, ¶27). The complaint states these exhibits contain charts that compare the "Exemplary" patent claims to the "Exemplary Defendant Products" (Compl. ¶17, ¶26). Without these exhibits, a detailed element-by-element analysis of the infringement allegations is not possible based on the complaint alone.

No probative visual evidence provided in complaint.

Identified Points of Contention

Based on the patent claims and the general nature of the technology, the infringement analysis may raise several questions:

• Technical Questions: What is the specific mechanism by which the accused products buffer image data and signal a host processor? Does this mechanism rely on a counter that tracks the quantity of data and compares it to a threshold, as described in the patents' embodiments, or does it use a different trigger, such as a fixed time interval or the completion of a full data line?
• Scope Questions: How should the term "signal generator" be construed? Does it require a dedicated hardware component as depicted in the patent's figures, or could it read on a software routine executed by a processor? Similarly, does the "circuit for controlling the transfer" require a distinct hardware controller within the interface, or can it comprise a combination of logic and processor-executed instructions?

V. Key Claim Terms for Construction

"in response to the quantity of data in the memory" (’790 Patent, Claim 1)

• Context and Importance: This phrase is central to defining the causal link between the data buffering and the processor notification. Its construction will determine whether infringement requires a direct quantitative measurement or if a more general temporal relationship suffices. Practitioners may focus on this term because it establishes the core "smart" functionality of the interface beyond simple storage.
• Intrinsic Evidence for Interpretation:
  • Evidence for a Broader Interpretation: The plain language of the claim and the summary of the invention could be argued to cover any system where the signal is generated as a consequence of data accumulating in the memory, not necessarily at a precise, measured threshold (’790 Patent, col. 2:8-10).
  • Evidence for a Narrower Interpretation: The detailed description of the preferred embodiment discloses a specific implementation where an "interrupt generator 48 compares the FIFO counter output Sc and the FIFO limit S₁" to generate the interrupt signal. This explicit comparison could be used to argue that the claim requires a direct, quantitative check (’790 Patent, col. 5:11-18; Fig. 2).

"a circuit for controlling the transfer of the data" (’790 Patent, Claim 1)

• Context and Importance: This term defines the component responsible for managing the data offload from the interface's memory to the processor system. The scope of "circuit" will be critical for determining whether the claims cover systems where this control function is distributed between dedicated hardware and processor-executed software.
• Intrinsic Evidence for Interpretation:
  • Evidence for a Broader Interpretation: The term "circuit" is used at a high level, and one might argue it should be given its ordinary meaning, which could encompass a collection of interacting components, including a processor running software, that collectively perform the control function.
  • Evidence for a Narrower Interpretation: The patent figures consistently depict this functionality as discrete hardware blocks within the interface, such as the "FIFO Read Control" (47) and "Chip Command Decoder" (45). This could support an argument that the term requires a self-contained hardware controller, distinct from the main processor system (’790 Patent, Fig. 2).

VI. Other Allegations

Indirect Infringement

The complaint alleges that Defendant induces infringement by distributing "product literature and website materials" that instruct end users to operate the accused products in a manner that infringes the patents (Compl. ¶15, ¶24).

Willful Infringement

The complaint bases its willfulness allegation on Defendant's knowledge of the patents acquired "at least since being served by this Complaint" and its continued infringing activity thereafter (Compl. ¶14-16, ¶23-25). This asserts a claim for post-filing willfulness.

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

• A primary issue in the early stages will be one of evidentiary development: because the complaint lacks specific details about the accused products, initial discovery will be critical for the Plaintiff to establish the precise hardware and software architecture of the accused systems and to map that architecture to the patent claims.
• The case may turn on a question of causality and scope: can the claim phrase "in response to the quantity of data" be construed to cover any system where a transfer is triggered after data accumulation, or does the patent’s specification limit it to a direct, quantitative comparison between a data count and a predefined limit?
• A final key question will be one of structural definition: does the claimed "circuit for controlling the transfer" require a distinct, dedicated hardware controller as depicted in the patent’s embodiments, or is the term broad enough to encompass control functions distributed across hardware and software in the accused system?