Cedar Lane Tech Inc v. Denso Intl America Inc

I. Executive Summary and Procedural Information

• Parties & Counsel:
  • Plaintiff: Cedar Lane Technologies Inc. (Canada)
  • Defendant: Denso International America, Inc. (Delaware)
  • Plaintiff’s Counsel: O'Kelly Ernst & Joyce
• Case Identification: 1:19-cv-01941, D. Del., 10/14/2019
• Venue Allegations: Venue is alleged to be proper in the District of Delaware because Defendant is a Delaware corporation and thus resides in the state.
• Core Dispute: Plaintiff alleges that Defendant’s Driver Status Monitor infringes patents related to a host interface for imaging arrays that manages data transfer between an image sensor and a processor system.
• Technical Context: The technology concerns integrated circuits for digital imaging, specifically addressing the data-rate mismatch between CMOS image sensors and general-purpose computer processors.
• Key Procedural History: The patents-in-suit share a common specification, with U.S. Patent No. 8,537,242 being a divisional of the application that issued as U.S. Patent No. 6,972,790. No other significant procedural history is mentioned in the complaint.

Case Timeline

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

U.S. Patent No. 6,972,790 - "Host interface for imaging arrays," issued December 6, 2005

The Invention Explained

• Problem Addressed: The patent describes a technical incompatibility between the continuous, high-rate "video style output" of CMOS image sensors and the data interface of commercial microprocessors, which are designed for random memory access. This mismatch traditionally required "additional glue logic," which diminished the cost-effectiveness and integration benefits of CMOS technology (’790 Patent, col. 1:47-66).
• The Patented Solution: The invention is an interface, preferably integrated on the same semiconductor die as the image sensor, that acts as a buffer. It comprises a memory (e.g., a FIFO buffer) that stores image data at the high rate dictated by the sensor's clock signals. It then generates a signal to a processor system, which can then read the data from the memory at its own, different rate, thereby decoupling the sensor's timing from the processor's operations (’790 Patent, Abstract; col. 2:4-14).
• Technical Importance: This approach allows for more efficient integration of image sensors into computer systems by managing data flow on-chip, reducing the need for external interface components and freeing the main processor for other tasks (’790 Patent, col. 2:25-30).

Key Claims at a Glance

• Independent Claim 1 is asserted (Compl. ¶13).
• Claim 1 breaks down into these essential elements:
  • An interface for receiving data from an image sensor and transferring it to a processor system.
  • A memory for storing imaging array data and clocking signals at a rate determined by the clocking signals.
  • A signal generator that generates a signal for the processor system in response to the quantity of data in the memory.
  • A circuit for controlling the transfer of data from the memory at a rate determined by the processor system.
• The complaint reserves the right to assert other claims (Compl. ¶13).

U.S. Patent No. 8,537,242 - "Host interface for imaging arrays," issued September 17, 2013

The Invention Explained

• Problem Addressed: As a divisional of the '790 Patent, the '242 Patent addresses the same problem: the data transfer incompatibility between CMOS image sensors and host processors, which requires additional external circuitry (’242 Patent, col. 1:44-63).
• The Patented Solution: The solution is a method of processing imaging signals that mirrors the function of the '790 Patent's apparatus. The method involves receiving image data, storing it in a FIFO memory, using a counter to track the amount of stored data, and then generating a signal to initiate the transfer of that data to a processor when a certain data level is reached (’242 Patent, Abstract; col. 8:1-8).
• Technical Importance: The claimed methods provide two distinct protocols for managing data transfer—one using a processor interrupt and another using a bus arbitration request—offering different implementation strategies for the same core buffering concept (’242 Patent, col. 6:25-46).

Key Claims at a Glance

• Independent Claims 1 and 8 are asserted (Compl. ¶23).
• Claim 1 breaks down into these essential method steps:
  • Receiving image data from an imaging array.
  • Storing the image data in a FIFO memory.
  • Updating a FIFO counter based on memory reads and writes.
  • Comparing the FIFO counter to a FIFO limit.
  • Generating an "interrupt signal" to a processor based on the comparison.
  • Transferring image data from the FIFO memory in response to the "interrupt signal".
• Claim 8 breaks down into similar steps, with a key difference in the signaling and transfer steps:
  • Generating a "bus request signal" to a bus arbitration unit based on the counter/limit comparison.
  • Transferring image data to an output bus in response to receiving a "grant signal" from the bus arbitration unit.
• The complaint reserves the right to assert other claims (Compl. ¶23).

III. The Accused Instrumentality

• Product Identification: The complaint identifies "at least Denso's Driver Status Monitor" as an exemplary accused product (Compl. ¶13).
• Functionality and Market Context: The complaint does not describe the specific technical functionality of the Driver Status Monitor. It is identified as a product made, used, sold, or imported by the Defendant (Compl. ¶13). The complaint alleges that Defendant distributes product literature and website materials related to the accused products (Compl. ¶16). No probative visual evidence provided in complaint.

IV. Analysis of Infringement Allegations

The complaint references but does not attach claim chart exhibits (Compl. ¶¶ 19-20, 29-30). The following tables are constructed from the asserted claims and the general allegations against the accused product.

’790 Patent Infringement Allegations

’242 Patent Infringement Allegations (Claim 1)

’242 Patent Infringement Allegations (Claim 8)

• Identified Points of Contention:
  • Technical Questions: A primary question will be evidentiary: what specific components and processes within the accused Driver Status Monitor correspond to the claimed "memory", "signal generator", and control "circuit" of the '790 Patent? The complaint does not provide these details.
  • Functional Questions: For the '242 Patent, the analysis will turn on the specific signaling protocol used by the accused product. Does it generate an "interrupt signal" to a processor as required by Claim 1, or does it generate a "bus request signal" to a "bus arbitration unit" as required by Claim 8? The complaint's assertion of both claims raises the question of whether the accused product employs one, the other, or a system that could be argued to meet the limitations of both.

V. Key Claim Terms for Construction

• The Term: "interface" (’790 Patent, Claim 1)

  • Context and Importance: This term defines the overall apparatus. Its construction will determine whether the claim covers only a single, integrated component or a collection of discrete components that work together. Practitioners may focus on this term because the patent emphasizes integration on a single die as a key benefit.
  • Intrinsic Evidence for Interpretation:
    • Evidence for a Broader Interpretation: The claim language itself does not require the interface to be a single, monolithic component, only that it perform the recited functions of receiving, storing, signaling, and controlling transfer (’790 Patent, col. 8:3-17).
    • Evidence for a Narrower Interpretation: The specification repeatedly emphasizes that a benefit of the invention is integrating the interface "on the same die as the imaging array sensor" and on a "single substrate," which may support an argument that the term implies a physically integrated unit (’790 Patent, col. 1:61-63; col. 2:28-30).

• The Term: "interrupt signal" vs. "bus request signal" (’242 Patent, Claims 1 and 8)

  • Context and Importance: The distinction between these two signals defines two mutually exclusive embodiments detailed in the patent. An "interrupt signal" is a direct request for a processor's attention (’242 Patent, Fig. 1, item 17), while a "bus request signal" is a request to a separate "bus arbitration unit" for control of the system bus (’242 Patent, Fig. 6, item SBR). The viability of the infringement allegations against the '242 Patent depends on the type of signaling protocol the accused product actually uses.
  • Intrinsic Evidence for Interpretation:
    • The specification provides distinct diagrams and descriptions for each type of signaling. The interrupt-based system is shown in Figure 2, where the "interrupt generator" (48) signals the CPU (10). The bus request system is shown in Figure 7, where the "bus request generator" (64) signals a "bus command unit" (45) after receiving an acknowledgment from a separate bus arbitration unit (’242 Patent, col. 5:11-18, col. 6:25-40). This clear delineation suggests the terms have distinct technical meanings that are not interchangeable.

VI. Other Allegations

• Indirect Infringement: The complaint alleges both induced and contributory infringement. Inducement is based on Defendant allegedly selling the accused products and distributing "product literature and website materials inducing end users" to operate them in an infringing manner (Compl. ¶¶17, 27). Contributory infringement is alleged on the basis that the accused products are "not a staple article of commerce suitable for substantial non-infringing use" (Compl. ¶¶18, 28).
• Willful Infringement: The complaint does not use the word "willful" but alleges that service of the complaint constitutes actual knowledge of infringement. It further alleges that Defendant's infringement has continued "Despite such actual knowledge," which may form the basis for a claim of post-filing willfulness (Compl. ¶¶16, 26).

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

1. Evidentiary Sufficiency: A threshold issue is whether the complaint's general allegations, which lack specific technical details linking the accused product's features to claim limitations, can survive a motion to dismiss. The case will depend on evidence, discovered later, that maps the internal architecture of the "Driver Status Monitor" to the patent claims.

2. Divergent Infringement Theories: For the '242 patent, a central question is one of technical implementation. Plaintiff has accused a single product of infringing two claims (1 and 8) that recite distinct, and likely mutually exclusive, signaling methods ("interrupt signal" vs. "bus request signal"). The case will likely require a determination of which, if either, of these specific technical pathways is practiced by the accused product.

3. Claim Scope and Integration: For the '790 patent, a key question will be one of definitional scope. Will the term "interface" be construed broadly to cover any set of components performing the claimed functions, or will it be narrowed by the specification's emphasis on physical integration onto a single semiconductor die with the image sensor? The answer will define the breadth of apparatuses that can be found to infringe.