Uusi LLC v. Apple Inc

I. Executive Summary and Procedural Information

• Parties & Counsel:
  • Plaintiff: UUSI, LLC D/B/A NARTRON (Michigan)
  • Defendant: Apple Inc. (California)
  • Plaintiff’s Counsel: Honigman Miller Schwartz and Cohn LLP; McKool Smith, P.C.
• Case Identification: 3:18-cv-04637, E.D. Mich., 11/22/2017
• Venue Allegations: Venue is alleged to be proper in the Eastern District of Michigan because Apple maintains regular and established places of business, such as Apple Stores, within the district and has committed alleged acts of patent infringement there.
• Core Dispute: Plaintiff alleges that Defendant’s iPhone, iPad, and iPod product lines, which incorporate capacitive touchscreens, infringe a patent related to electronic switching circuits designed to improve touch detection reliability.
• Technical Context: The technology concerns capacitive touch sensors, specifically methods to mitigate false actuations caused by surface contaminants like moisture or skin oils by operating the sensor at high frequencies.
• Key Procedural History: The asserted patent has an extensive post-issuance history mentioned in the complaint. It underwent two ex parte reexaminations, resulting in the issuance of two reexamination certificates. The patent expired in 2016, limiting any potential recovery to past damages. The complaint also notes that the patent was the subject of an inter partes review (IPR) proceeding initiated by a third party, which concluded with a Final Written Decision shortly before the complaint was filed. Plaintiff alleges that this decision affirmed the patentability of all instituted claims. Finally, the complaint alleges that Plaintiff provided Defendant with notice of the patent and its alleged infringement as early as 2007.

Case Timeline

Date	Event
1996-01-31	'183 Patent Priority Date
1998-08-18	'183 Patent Issue Date
2007 (approx.)	Plaintiff provides notice of '183 Patent to Defendant
2013-04-29	'183 C1 Reexamination Certificate Issue Date
2014-06-27	'183 C2 Reexamination Certificate Issue Date
2016-01-31	'183 Patent Expiration Date
2016-04-15	Third party (Samsung) files IPR petition on '183 Patent
2017-10-18	PTAB issues IPR Final Written Decision
2017-11-22	Complaint Filing Date

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

U.S. Patent No. 5,796,183 - "Capacitive Responsive Electronic Switching Circuit"

The Invention Explained

• Problem Addressed: The patent's background section describes a problem with prior art capacitive touch switches, particularly when used in dense arrays like keyboards. It states that surface contamination from skin oils, water, or other materials can create conductive films that couple adjacent touch pads, leading to unintended or multiple actuations when only a single touch is desired (’183 Patent, col. 4:14-24).
• The Patented Solution: The invention proposes to solve this problem by operating the touch-sensing circuit at a relatively high frequency, specified as 50 kHz or greater, and preferably 800 kHz or greater (’183 Patent, col. 5:48-52). The specification explains that at these higher frequencies, the impedance of the intended capacitive path (through the glass and the user's body) drops significantly, while the impedance of a contaminant path (which is primarily resistive) remains high. This large difference in impedance allows the detection circuit to more reliably distinguish a true touch from a false signal caused by surface contamination (’183 Patent, col. 8:10-24).
• Technical Importance: This high-frequency approach offered a potential method to improve the robustness and reliability of capacitive touch sensors, a key factor for their successful implementation in consumer devices used in uncontrolled environments (’183 Patent, col. 7:15-18).

Key Claims at a Glance

• The complaint’s infringement allegations focus on independent claim 40, which was added during ex parte reexamination (Compl. ¶¶ 10, 19).
• The essential elements of independent claim 40 (per the C2 Reexamination Certificate) include:
  • An oscillator providing a periodic signal at a predefined frequency.
  • A microcontroller that uses the oscillator's signal to selectively provide signal output frequencies to rows of input touch terminals on a keypad.
  • A plurality of input touch terminals on a dielectric substrate that define adjacent areas for user input.
  • A detector circuit, coupled to the oscillator and touch terminals, that is responsive to the presence of an operator's body capacitance to ground to provide a control signal.
  • The selection of oscillator and signal output frequencies to decrease the impedance of the dielectric substrate relative to the impedance of any contaminant.
  • The detector circuit comparing a sensed body capacitance change to a threshold level to prevent inadvertent actuation.
• The complaint alleges infringement of "one or more claims" but its substantive theory is directed to claim 40 (Compl. ¶17).

III. The Accused Instrumentality

Product Identification

• The "Accused Products" are identified as the Apple iPhone, Apple iPod, and Apple iPad product lines, including numerous specific models from the iPhone 5 to the iPhone 6s Plus, various iPod Touch and nano models, and various iPad, iPad mini, and iPad Air models (Compl. ¶17).

Functionality and Market Context

• The complaint alleges that the Accused Products contain capacitive touchscreens that allow users to make selections by moving a finger near or in contact with the screen (Compl. ¶18).
• It is alleged on "information and belief" that these products utilize touch controller chips, such as those from Broadcom and Texas Instruments, which perform the functions recited in the asserted patent claims (Compl. ¶19). Specifically, the complaint alleges these controllers take a periodic signal from an oscillator, provide signals to input touch terminals, and use a detector circuit to respond to the user's body capacitance to ground to generate a control signal (Compl. ¶19).
• The complaint alleges the Accused Products use input and output frequencies selected such that the change in impedance from a user's touch differs from impedance changes caused by contaminants on the substrate (Compl. ¶19).

IV. Analysis of Infringement Allegations

No probative visual evidence provided in complaint.

Claim Chart Summary

The complaint provides a narrative infringement theory in paragraph 19, which is summarized below in a claim chart format for the asserted independent claim 40.

Claim Element (from Independent Claim 40)	Alleged Infringing Functionality	Complaint Citation	Patent Citation
an oscillator providing a periodic output signal having a predefined frequency;	The touchscreen controller takes a periodic signal from an oscillator with a pre-defined frequency.	¶19	col. 25:9-11
a microcontroller...selectively providing signal output frequencies to each row of input touch terminals.	The touchscreen controller...selectively provides a signal output frequency to each row of input touch terminals.	¶19	col. 25:12-19
the plurality of input touch terminals defining adjacent areas on a dielectric substrate for a user to provide inputs.	On the touchscreen of the Accused Products, the input touch terminals define adjacent areas on a substrate for a user to provide inputs.	¶19	col. 25:20-23
a detector circuit...responsive to signals from said oscillator...and the presence of the user's body capacitance to ground to provide a control output signal.	When touched...by the user, a detector circuit within the Accused Products respond to signals from the oscillator through the touchscreen controller and the presence of the user's body capacitance to ground to provide a control output signal.	¶19	col. 25:24-32
wherein said...frequencies are selected such that the change in impedance caused by the user's touch differs from any change in impedance that may create an electrical path caused by contaminates on the substrate.	The Accused Products use input and output frequencies such that the change in impedance caused by the user's touch differs from any change in impedance that may create an electrical path caused by contaminates on the substrate.	¶19-10	col. 25:33-41

Identified Points of Contention

• Scope Questions: A primary question may be whether the claim term "keypad", which the patent illustrates with examples like industrial palm buttons and keyboards, can be construed to read on the general-purpose, graphical touchscreens of the Accused Products (’183 Patent, col. 7:55-57). Another question is whether the architecture of Apple's touch controllers aligns with the claim's specific requirement of a microcontroller that "selectively provides a signal output frequency to each row of input touch terminals."
• Technical Questions: The complaint alleges on "information and belief" that the Accused Products function in the claimed manner. A central technical question will be what evidence demonstrates that Apple's devices were designed to select operating frequencies specifically for the purpose of differentiating a user's touch from the impedance of surface contaminants, as required by the final limitation of claim 40.

V. Key Claim Terms for Construction

The Term: "keypad"

• Context and Importance: This term's construction is critical to the scope of the patent. If construed narrowly to mean a set of discrete, fixed-location keys (like a computer keyboard or calculator), it may not cover the dynamic, multi-function graphical interface of a smartphone. If construed broadly, it could encompass any array of touch-sensitive locations. Practitioners may focus on this term because the patent's primary examples are keyboards and industrial buttons, contexts that are arguably different from a modern smartphone's touchscreen (’183 Patent, col. 5:37, col. 7:57).
• Intrinsic Evidence for Interpretation:
  • Evidence for a Broader Interpretation: The patent describes employing "a multiplicity of small sized touch terminals in a physically close array such as a keyboard," which may be argued as an illustrative example rather than a limiting definition (’183 Patent, col. 5:55-58).
  • Evidence for a Narrower Interpretation: The repeated use of "keyboard" and "palm button" as the problems to be solved and the primary applications described could support a narrower construction limited to such structured, button-based interfaces (’183 Patent, col. 4:30-34, col. 5:37-39).

The Term: "detector circuit compares a sensed body capacitance change...to a threshold level"

• Context and Importance: This term defines the specific logical operation for making a touch determination. Infringement will depend on whether the accused detector circuits perform this specific comparison to a "threshold level" to prevent inadvertent generation of a control signal, or if they use a different method for filtering noise and confirming a touch.
• Intrinsic Evidence for Interpretation:
  • Evidence for a Broader Interpretation: The specification discusses setting a "detection threshold for the touched pad...well below that of an adjacent pad," suggesting the "threshold" is a general concept of signal level differentiation (’183 Patent, col. 11:5-8).
  • Evidence for a Narrower Interpretation: The reexamined claim language explicitly requires a "compares...to a threshold level" step to "prevent inadvertent generation of the control output signal," which could be argued to require a specific, dedicated hardware or software mechanism for this comparison, beyond general signal processing (’183 Patent, C2 Cert., col. 2:52-56).

VI. Other Allegations

• Indirect Infringement: The complaint alleges inducement of infringement based on Defendant's "online user manuals, marketing materials, and help materials," which allegedly instruct customers on how to use the Accused Products in an infringing manner (Compl. ¶22). Contributory infringement is also alleged, on the basis that the Accused Products constitute a material part of the invention and are not staple articles of commerce with substantial non-infringing uses (Compl. ¶23).
• Willful Infringement: Willfulness is alleged based on pre-suit knowledge. The complaint asserts that Plaintiff notified Defendant of the '183 patent and the alleged infringement in 2007, and that Defendant subsequently refused to enter licensing discussions (Compl. ¶24).

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

• A core issue will be one of definitional scope: can the term "keypad," which is described in the patent in the context of keyboards and industrial buttons, be construed to cover the dynamic, graphical touchscreen interfaces of the accused smartphone and tablet products?
• A key evidentiary question will be one of operational proof: can Plaintiff, through discovery, demonstrate that the accused touch controllers in Apple's products perform the specific functions recited in claim 40, particularly the selection of frequencies for the explicit purpose of mitigating contaminant-based interference and the use of a row-by-row signal driving architecture?
• A foundational question, arising from the extensive procedural history cited in the complaint, will concern the validity and final scope of the asserted claims. The litigation will need to resolve the patent's standing following multiple reexaminations and an inter partes review, the outcome of which is characterized by the Plaintiff as favorable but occurred shortly before the suit was filed.