Slingshot Printing LLC v. Canon USA Inc

I. Executive Summary and Procedural Information

• Parties & Counsel:
  • Plaintiff: Slingshot Printing LLC (Delaware)
  • Defendant: Canon U.S.A., Inc. (New York) and Canon Solutions America, Inc. (New York)
  • Plaintiff’s Counsel: Hecht Partners, LLP
• Case Identification: 2:22-cv-01852, E.D.N.Y., 04/01/2022
• Venue Allegations: Venue is alleged to be proper as Defendants are incorporated in New York, maintain headquarters within the Eastern District of New York, and have allegedly committed acts of patent infringement in the district.
• Core Dispute: Plaintiff alleges that Defendants’ inkjet printers, printheads, and associated ink cartridges infringe three patents related to the design and thermal management of heater chips within inkjet printheads.
• Technical Context: The technology concerns the physical layout of heating elements and temperature sensors on the semiconductor chips used in inkjet printheads to control the ejection of ink droplets.
• Key Procedural History: The complaint notes that the Patents-in-Suit were originally assigned to Lexmark International, Inc., subsequently acquired by Funai Electric Co., Ltd., and later assigned to Plaintiff Slingshot Printing LLC, which describes itself as being in the business of licensing patented technology.

Case Timeline

Date	Event
2005-09-30	U.S. Patent 7,290,864 Priority Date
2005-12-30	U.S. Patent 7,484,823 Priority Date
2005-12-30	U.S. Patent 7,594,708 Priority Date
2007-11-06	U.S. Patent 7,290,864 Issued
2009-02-03	U.S. Patent 7,484,823 Issued
2009-09-29	U.S. Patent 7,594,708 Issued
2022-04-01	Complaint Filed

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

U.S. Patent No. 7,484,823 - Methods and Apparatuses for Regulating the Temperature of Multi-Via Heater Chips (issued Feb. 3, 2009)

The Invention Explained

• Problem Addressed: The patent describes a challenge in high-resolution inkjet printheads that place heater arrays on both sides of an ink channel ("via"). In such designs, accurately sensing and regulating the operating temperature is difficult. Prior art sensors were either too far away (providing only a general chip average) or too close to a single heater, leading to inaccurate readings influenced by thermal crosstalk from adjacent printing activity (’823 Patent, col. 2:35-54).
• The Patented Solution: The invention proposes placing a temperature sensing element within the silicon region between two adjacent heater arrays. The sensor is positioned "substantially centrally" in this region, away from the direct influence of either array, to obtain a more accurate temperature reading for that specific zone. This enables more precise, region-by-region thermal regulation using, for example, non-nucleating heating pulses to maintain optimal ink viscosity and drop size (’823 Patent, Abstract; col. 6:1-30).
• Technical Importance: This design approach allows for finer thermal control in densely packed, multi-via printheads, which is critical for achieving consistent print quality and higher resolutions (’823 Patent, col. 2:41-54).

Key Claims at a Glance

• The complaint asserts independent claim 1 (Compl. ¶23).
• The essential elements of independent claim 1 include:
  • a first heater array positioned substantially adjacent a first via;
  • a second heater array positioned substantially adjacent a second via;
  • a region, positioned between the first and second heater arrays;
  • a temperature sensing element operable to sense the temperature of the region, where the sensing element is "substantially centrally disposed" with respect to the region; and
  • the first and second heater arrays are operable to receive heating responsive to the sensed temperature to regulate the region's temperature.
• The complaint reserves the right to assert dependent claims 2-3, 5-6, 8-13, and 15-17 (Compl. ¶23).

U.S. Patent No. 7,594,708 - Methods and Apparatuses for Sensing Temperature of Multi-Via Heater Chips (issued Sep. 29, 2009)

The Invention Explained

• Problem Addressed: Similar to the ’823 Patent, this patent addresses the need for accurate temperature monitoring in multi-via printheads where thermal crosstalk between adjacent color channels can degrade print quality (’708 Patent, col. 2:35-54).
• The Patented Solution: The invention claims a printhead chip having a plurality of parallel ink vias, with heater arrays on both longitudinal sides of each via. A single temperature sensing element is disposed within each silicon region between adjacent ink vias. By placing a single sensor at a predetermined distance from the adjacent heater arrays, the system can sense a temperature "representative of the heater arrays adjacent to the region" and regulate it accordingly (’708 Patent, Abstract; col. 7:26-40).
• Technical Importance: The technology provides a method for discrete, region-based thermal management on a complex printhead, facilitating the higher print resolutions made possible by dual-sided heater array configurations (’708 Patent, col. 2:41-54).

Key Claims at a Glance

• The complaint asserts independent claim 1 (Compl. ¶42).
• The essential elements of independent claim 1 include:
  • a plurality of ink vias arranged parallel to one another;
  • a heater array disposed adjacent each longitudinal side of the ink vias;
  • a region disposed adjacent each heater array, with only one region between two adjacent ink vias; and
  • a "single temperature sensing element disposed within each region" operable to sense a temperature representative of the adjacent heater arrays.
• The complaint reserves the right to assert dependent claims 2-3, 5-6, 8-12, and 14-15 (Compl. ¶42).

U.S. Patent No. 7,290,864 - Heater Chips With a Reduced Number of Bondpads (issued Nov. 6, 2007)

Technology Synopsis

The patent addresses the problem that conventional heater chips require a large number of electrical connection points ("bondpads") to power the heater arrays, which increases chip size and manufacturing cost (’864 Patent, col. 1:35-42). The invention discloses a more efficient layout where a single bondpad supplies power to heater arrays on opposing sides of an ink via, thereby reducing the total number of bondpads required for a multi-array chip (’864 Patent, Abstract; col. 5:36-50).

Asserted Claims

Independent claims 1, 8, and 16 are asserted (Compl. ¶61).

Accused Features

The complaint accuses Canon products containing a printhead with "at least one bond pad connecting to heaters positioned on opposing sides of an ink via" of infringement (Compl. ¶61(v)).

III. The Accused Instrumentality

Product Identification

The complaint identifies a broad range of Canon products, including the Maxify, Pixma, and imagePROGRAF lines of inkjet printers, as well as their corresponding ink cartridges and printheads (Compl. ¶18). Specific examples include the PF-10 printhead and numerous ink cartridges (e.g., CL-211, CL-261) and printer models (e.g., Pixma TR7020, Maxify iX6820) (Compl. ¶23, 42, 61).

Functionality and Market Context

The accused instrumentalities are inkjet printing devices and their consumable components that accomplish printing by ejecting ink from a printhead (Compl. ¶9). The complaint notes that in some products, the printhead is integrated into the ink cartridge, while in others it is a separate component within the printer (Compl. ¶20). These products are alleged to be marketed and sold for consumer, office, and professional use throughout the United States (Compl. ¶18, 21).

IV. Analysis of Infringement Allegations

The complaint references claim chart exhibits (Exhibits D, E, and F) as providing the factual basis for infringement, but these exhibits were not filed with the complaint itself (Compl. ¶25, 44, 63). The infringement theories are therefore summarized from the complaint's narrative allegations. No probative visual evidence provided in complaint.

'823 Patent Infringement Allegations

The complaint alleges that certain Canon printheads, such as the PF-10, infringe the ’823 patent because they contain a chip with a specific structure. The alleged structure includes at least three parallel ink vias, where the area between the first and second vias contains a "first temperature sensing element substantially centrally disposed between first and second columns of heater actuators" (Compl. ¶23(v)). A similar structure with a second temperature sensor is alleged to exist between the second and third vias (Compl. ¶23(v)). This narrative description mirrors the elements of asserted claim 1.

• Identified Points of Contention:
  • Scope Questions: A potential dispute may arise over the term "substantially centrally disposed." The infringement analysis may turn on whether the physical placement of the sensors in the accused products meets the degree of centrality required by the claim as construed by the court.
  • Technical Questions: The complaint's allegations focus on the physical structure. A key technical question is whether the accused temperature sensors function as claimed—specifically, whether their output is used to control "heating responsive to the temperature of the region" for thermal regulation, as required by the final limitation of claim 1.

'708 Patent Infringement Allegations

The infringement theory against the ’708 patent is also structural. The complaint alleges that accused Canon printheads include a chip with "at least two ink vias having a column of heater actuators on each side of the vias and a single temperature sensing element adjacent and substantially parallel to each column of heater actuators" (Compl. ¶42(iv)). This allegation attempts to map the accused products onto the elements of asserted claim 1 of the ’708 patent.

• Identified Points of Contention:
  • Scope Questions: Claim 1 requires a "single temperature sensing element disposed within each region" between ink vias. A point of contention may be whether the accused configuration of a sensor "adjacent and substantially parallel" to heater columns satisfies the "disposed within" limitation.
  • Technical Questions: As with the ’823 patent, a central question will be evidentiary. What evidence shows that the accused sensor is a "single" element for each region and that it senses a "temperature representative of the heater arrays adjacent to the region," as opposed to serving a different purpose like general overheat protection?

V. Key Claim Terms for Construction

'823 Patent, Claim 1

• The Term: "substantially centrally disposed"
• Context and Importance: The location of the temperature sensor relative to the surrounding heater arrays is a core aspect of the invention's solution to thermal crosstalk. The interpretation of this term of degree will be critical for determining infringement. Practitioners may focus on this term because its construction could be dispositive; a narrow definition might place the accused devices outside the claim scope, while a broad one may support the plaintiff's case.
• Intrinsic Evidence for Interpretation:
  • Evidence for a Broader Interpretation: The specification's objective is to place the sensor "well away from the heater arrays" to get an accurate reading for the entire region (’823 Patent, col. 6:61-62). This functional goal may support a broader construction not tied to strict geometric centrality.
  • Evidence for a Narrower Interpretation: The patent figures and detailed description use the word "centered" when describing the placement of the sensors within their respective thermal regions, which could support a more restrictive, geometric interpretation (’823 Patent, col. 7:1-4; Fig. 5).

'708 Patent, Claim 1

• The Term: "a single temperature sensing element disposed within each region"
• Context and Importance: This phrase defines the number and location of the sensors claimed by the invention. The dispute will likely focus on whether the architecture of the accused Canon printheads meets both the "single" and the "within" requirements for each defined region between vias.
• Intrinsic Evidence for Interpretation:
  • Evidence for a Broader Interpretation: The term "within" could be argued to mean anywhere in the silicon area bounded by two adjacent ink vias, supporting a more flexible placement.
  • Evidence for a Narrower Interpretation: The specification and figures consistently depict one discrete sensing element for each defined region (e.g., sensor 542 in region 432) (’708 Patent, Fig. 5). A defendant could argue this supports a narrow reading where any deviation, such as a sensor that spans regions or the use of multiple sensors per region, would not infringe.

VI. Other Allegations

• Indirect Infringement: The complaint alleges inducement of infringement for all three patents. It asserts that Defendants provide customers and distributors with products, user guides, manuals, and technical support that instruct and encourage use of the products in an infringing manner (Compl. ¶28-29, 47-48, 66-67).
• Willful Infringement: The complaint pleads facts to support willfulness by alleging that Defendants had knowledge of the patents. This knowledge is alleged to have occurred at least upon service of the complaint and, on information and belief, pre-suit, due to Defendants' alleged practice of monitoring the patent landscape (Compl. ¶27, 46, 65). The complaint further alleges Defendants acted with "actual intent to cause the acts that it knows or should know would induce direct infringement and/or willful blindness" (Compl. ¶30, 49, 68).

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

• A core issue will be one of claim construction: can the term "substantially centrally disposed" from the ’823 patent and "a single temperature sensing element disposed within each region" from the ’708 patent be construed to read on the specific physical layouts of Canon's printhead sensor architectures? The outcome of the Markman hearing on these terms may significantly shape the dispute.
• A second key issue will be one of structural and functional proof: beyond establishing the physical placement of components, the case may turn on evidence demonstrating functional correspondence. This includes whether a single bondpad powers heaters on opposing sides of a via as claimed in the ’864 patent, and whether the accused temperature sensors are, in fact, used for the specific, region-based thermal regulation disclosed in the ’823 and ’708 patents.
• An underlying question concerns the commercial context of the dispute. Given that the patents originated with a market competitor (Lexmark) and are now being asserted by a licensing entity, the litigation may focus heavily on establishing the technological value and calculating a potential reasonable royalty for the alleged infringement.