Cedar Lane Tech Inc v. Ambir Technology Inc

I. Executive Summary and Procedural Information

• Parties & Counsel:
  • Plaintiff: Cedar Lane Technologies Inc. (Canada)
  • Defendant: Ambir Technology, Inc. (Illinois)
  • Plaintiff’s Counsel: Rabicoff Law LLC
• Case Identification: 1:21-cv-05457, N.D. Ill., 10/14/2021
• Venue Allegations: Venue is asserted based on Defendant having an established place of business in the Northern District of Illinois.
• Core Dispute: Plaintiff alleges that Defendant’s imaging products infringe patents related to an interface for managing the transfer of data from an image sensor to a processor system.
• Technical Context: The technology concerns methods and systems for efficiently connecting image sensors, such as CMOS sensors, to computer processors by using an intermediate memory buffer to reconcile differing data transfer rates.
• Key Procedural History: The complaint does not mention any prior litigation, inter partes review (IPR) proceedings, or licensing history related to the patents-in-suit. U.S. Patent No. 8,537,242 is a divisional of the application that resulted in U.S. Patent No. 6,972,790, indicating a close technical and prosecution relationship between the two patents.

Case Timeline

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 describes a fundamental incompatibility between the continuous, clock-synchronized video-style data output of an image sensor and the random-access, address-based data input of a commercial microprocessor. This mismatch traditionally required additional "glue logic," which increased cost and complexity, undermining the benefits of integrating a sensor and processor on a single chip. (’790 Patent, col. 1:47-66).
• The Patented Solution: The invention proposes an interface, preferably integrated on the same die as the image sensor, that acts as an intermediary. It uses a memory (such as a first-in-first-out, or FIFO, buffer) to temporarily store data from the sensor at the sensor's rate. The interface then generates a signal, such as an interrupt, to alert the main processor that data is ready. A control circuit then manages the data transfer from the buffer to the processor at a rate determined by the processor, effectively decoupling the two systems. (’790 Patent, Abstract; col. 2:4-14).
• Technical Importance: This architecture simplified the integration of image sensors with general-purpose computer systems, a key enabler for the development of cost-effective, compact digital imaging devices like system-on-a-chip cameras. (’790 Patent, col. 1:25-30, 60-63).

Key Claims at a Glance

• The complaint does not specify which claims of the ’790 Patent are asserted, instead referring to "Exemplary '790 Patent Claims" in an external exhibit not provided with the complaint (Compl. ¶12). Independent claim 1 is representative of the patent's core apparatus claims.
• Independent Claim 1:
  • An interface for receiving data from an image sensor having an imaging array and a clock generator for transfer to a processor system comprising:
  • 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 other claims, including any 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 application for the ’790 Patent, the ’242 Patent addresses the same technical problem of bridging the data transfer gap between image sensors and microprocessors. (’242 Patent, col. 1:11-63).
• The Patented Solution: The ’242 Patent claims the invention as a method. The described process involves receiving image data, storing it in a FIFO memory, using a counter to track the amount of stored data, comparing this count to a predefined limit, and then generating a signal (e.g., an interrupt or a bus request) to initiate the transfer of the buffered data to the processor. (’242 Patent, Abstract; col. 8:56-65).
• Technical Importance: This patent protects the operational process of the system described in the '790 Patent, providing a different scope of protection for the same core technological solution.

Key Claims at a Glance

• The complaint does not specify which claims of the ’242 Patent are asserted, referring to "Exemplary '242 Patent Claims" in an external exhibit not provided with the complaint (Compl. ¶21). Independent claim 1 is representative of the patent's interrupt-based method claims.
• Independent Claim 1:
  • A method of processing imaging signals, the method comprising:
  • 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 in the FIFO memory in response to memory reads and writes;
  • comparing the count of the FIFO counter with a FIFO limit;
  • generating an interrupt signal to request a processor to transfer image data from the FIFO memory...; and
  • transferring image data from the FIFO memory to the processor in response to the interrupt signal.
• The complaint reserves the right to assert other claims, including any dependent claims. (Compl. ¶21).

III. The Accused Instrumentality

Product Identification

The complaint does not identify any specific accused products by name. It refers generally to "Exemplary Defendant Products" that are identified in charts incorporated by reference as Exhibits 3 and 4, which were not provided with the complaint. (Compl. ¶12, ¶17, ¶21, ¶26).

Functionality and Market Context

The complaint alleges that Defendant makes, uses, sells, and imports products that practice the technology claimed by the patents-in-suit. (Compl. ¶12, ¶21). It further alleges that Defendant distributes "product literature and website materials" that instruct customers on how to use the products in a manner that infringes the patents. (Compl. ¶15, ¶24). The complaint does not provide sufficient detail for analysis of the products' specific functionality or market context.

IV. Analysis of Infringement Allegations

The complaint alleges infringement of both the ’790 and ’242 patents but incorporates claim charts by reference in Exhibits 3 and 4, which were not included in the provided filing (Compl. ¶18, ¶27). Therefore, a detailed element-by-element analysis based on the complaint's specific allegations is not possible. The infringement theory must be inferred from the general allegations. Plaintiff alleges that Defendant's "Exemplary Defendant Products" contain the necessary components and perform the necessary steps to meet all limitations of the asserted claims. (Compl. ¶17, ¶26).

No probative visual evidence provided in complaint.

• Identified Points of Contention:
  • Evidentiary Mapping: A primary point of contention will be establishing a factual basis for infringement. Without specific product details or claim charts, it is an open question what evidence Plaintiff will use to map the architecture and operation of Defendant's products onto the claim elements of the patents-in-suit.
  • Technical Implementation: For the ’790 Patent, a potential dispute may arise over whether the accused products contain a "memory," "signal generator," and "circuit for controlling" that correspond to the claimed structures. For the ’242 Patent's method claims, the dispute may focus on whether the accused products actually perform each of the discrete claimed steps, such as explicitly "comparing the count of the FIFO counter with a FIFO limit."

V. Key Claim Terms for Construction

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

  • Context and Importance: The scope of "interface" is central to determining what product architectures can infringe. Practitioners may focus on this term because its construction will determine whether it is limited to a dedicated hardware component or can encompass a combination of hardware and software.
  • Intrinsic Evidence for a Broader Interpretation: The claim language and specification describe the interface in functional terms, as a component "for receiving data... and for transferring the data," which may support a construction not tied to a specific physical implementation. (’790 Patent, col. 2:4-6).
  • Intrinsic Evidence for a Narrower Interpretation: The specification repeatedly emphasizes the benefit of integrating the interface "on the same die as the image sensor" and provides block diagrams (e.g., Fig. 2) showing discrete hardware components, which may support a narrower construction limited to a hardware-centric embodiment. (’790 Patent, Abstract; col. 2:28-30).

• Term: "circuit for controlling the transfer" (’790 Patent, Claim 1)

  • Context and Importance: The definition of this term will be critical for infringement. The question is what structures disclosed in the patent correspond to this function and what structures in the accused product are equivalent.
  • Intrinsic Evidence for a Broader Interpretation: The claim requires a circuit that performs the function of "controlling the transfer of the data from the memory at a rate determined by the processor system." (’790 Patent, col. 2:10-13). Plaintiff may argue this functional description should not be unduly limited.
  • Intrinsic Evidence for a Narrower Interpretation: The specification discloses corresponding structures including a "FIFO Read Control" (47), a "Chip Command Decoder" (45), and associated registers. (’790 Patent, Fig. 2; col. 5:45-60). Defendant may argue that the scope of this limitation is confined to these disclosed structures and their equivalents.

• Term: "generating an interrupt signal" (’242 Patent, Claim 1)

  • Context and Importance: Infringement of this method claim may depend on whether the notification mechanism in the accused product qualifies as an "interrupt signal" in its technical sense.
  • Intrinsic Evidence for a Broader Interpretation: The patent describes the signal's purpose as being to signal the CPU "that data is available for it to upload," which could arguably cover any software or hardware alert that serves this function. (’790 Patent, col. 4:19-21).
  • Intrinsic Evidence for a Narrower Interpretation: The patent specification explicitly distinguishes between an "interrupt signal" sent to a CPU (Fig. 2) and a "bus request signal" sent to a "bus arbitration unit" (Fig. 6). This distinction suggests that "interrupt signal" has a specific technical meaning that is narrower than any general processor alert. (’790 Patent, col. 5:12-18, col. 6:45-53).

VI. Other Allegations

• Indirect Infringement: The complaint alleges induced infringement for both patents. The factual basis asserted is that Defendant sells the accused products with accompanying "product literature and website materials" that allegedly instruct and encourage customers to use the products in a manner that directly infringes the patent claims. (Compl. ¶15, ¶16, ¶24, ¶25).
• Willful Infringement: The complaint alleges that infringement has been willful since Defendant gained knowledge of the patents. This knowledge is alleged to have been established, at the latest, by the service of the complaint and its accompanying (but unprovided) claim charts. (Compl. ¶14, ¶15, ¶23, ¶24). No allegations of pre-suit knowledge are made.

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

1. Evidentiary Burden: A central issue will be one of proof: given the complaint’s lack of specificity, what technical evidence can Plaintiff muster from discovery to demonstrate that the internal hardware and software operations of Defendant's unnamed products actually practice the specific elements and steps of the asserted claims?
2. Definitional Scope: The case may turn on a question of structural definition: can the term "circuit," as used in the ’790 Patent, be construed broadly to read on functions performed by software running on a general-purpose processor, or is its meaning confined to the dedicated hardware blocks disclosed in the patent’s embodiments?
3. Operational Equivalence: A key evidentiary question for the ’242 Patent will be one of functional operation: do the accused products manage data transfer by performing the specific patented method of comparing a buffer's data count to a pre-set limit to trigger a request, or do they achieve a similar outcome through a technically distinct process not covered by the claims?