NuCurrent Inc v. Sariana LLC

I. Executive Summary and Procedural Information

• Parties & Counsel:
  • Plaintiff: NuCurrent, Inc. (Illinois)
  • Defendant: Sariana LLC (Satechi) (California)
  • Plaintiff’s Counsel: Crosbie Gliner Schiffman Southard & Swanson LLP; Global IP Law Group, LLC
• Case Identification: 3:25-cv-00912, S.D. Cal., 04/17/2025
• Venue Allegations: Plaintiff alleges venue is proper in the Southern District of California because Defendant Sariana LLC has a regular and established place of business in the district.
• Core Dispute: Plaintiff alleges that Defendant’s Qi2-compliant wireless chargers infringe two patents related to technologies for dynamically tuning wireless power systems and altering power levels based on operating frequency.
• Technical Context: The patents concern high-efficiency wireless charging for consumer electronics, a technology central to standards like Qi2 which aim to improve charging speed, efficiency, and interoperability for devices like smartphones and accessories.
• Key Procedural History: The complaint alleges that the asserted patents are essential to the Qi2 wireless charging standard and that Plaintiff offered Defendant a license on reasonable and non-discriminatory (RAND) terms. Plaintiff further alleges it provided Defendant with multiple notices of infringement beginning in April 2024, which Defendant allegedly ignored, leading Plaintiff to characterize Defendant's actions as "classic hold-out behavior."

Case Timeline

Date	Event
2020-01-03	Earliest Priority Date for U.S. Patent 12,184,084
2020-04-30	Earliest Priority Date for U.S. Patent 12,272,970
2024-04-30	First notice of infringement sent to Defendant (Compl. ¶41)
2024-12-31	U.S. Patent 12,184,084 Issued (Compl. ¶20)
2025-01-27	Second notice of infringement sent to Defendant (Compl. ¶43)
2025-02-20	Third notice of infringement sent to Defendant (Compl. ¶46)
2025-04-08	U.S. Patent 12,272,970 Issued (Compl. ¶21)
2025-04-17	Complaint Filed

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

U.S. Patent No. 12,184,084, "Systems and methods for dynamically tuning a wireless power transfer system," Issued December 31, 2024

The Invention Explained

• Problem Addressed: The efficiency of wireless power transfer is sensitive to "disturbances" such as a varying distance between charging coils, changes in temperature, or the presence of foreign objects, which can degrade performance and create safety issues (’084 Patent, col. 1:60-col. 2:3).
• The Patented Solution: The invention describes a system that uses a "dynamic tuning controller" to actively manage the power transfer process. The controller receives data from various sensors (e.g., temperature, current, voltage sensors) to detect disturbances and, in response, adjusts "forward gain elements" of the system—such as the operating frequency or the capacitance of a tunable capacitor circuit—to maintain optimal and safe operation under variable conditions (’084 Patent, Abstract; col. 2:13-39). The detailed system diagram shows a controller receiving input from numerous sensors to tune various transmitter and receiver components (’084 Patent, Fig. 8).
• Technical Importance: This approach enables wireless chargers to be more robust, efficient, and safe in real-world consumer environments where conditions are not always ideal (’084 Patent, col. 2:4-12).

Key Claims at a Glance

• The complaint asserts independent claim 1 and dependent claims 6-13, 21, and 22 (Compl. ¶52).
• Independent Claim 1 of the ’084 Patent recites:
  • A voltage regulator operable to produce a supply voltage signal.
  • An inverter to produce a first AC signal.
  • A capacitor circuit comprising a bank of two or more capacitors, operable to tune the first AC signal to produce a second AC signal.
  • A transmission antenna to produce a wireless power signal.
  • At least one controller configured to define the configurable frequency, the configurable voltage level, and the configuration state of the bank of capacitors.

U.S. Patent No. 12,272,970, "Operating Frequency Based Power Level Altering In Extended Range Wireless Power Transmitters," Issued April 8, 2025

The Invention Explained

• Problem Addressed: Legacy wireless transmitters often have limited charging distances (3-5 mm) and lack granular power control, making them incompatible with many accessories or use cases. Furthermore, supporting higher power profiles traditionally required expensive and complex internal voltage regulation hardware, limiting compatibility with common "off-the-shelf" power supplies (’970 Patent, col. 2:5-24; col. 3:15-24).
• The Patented Solution: The invention discloses a wireless transmitter that offloads complex voltage regulation to an external power supply (e.g., a USB-PD adapter). The transmitter's controller sends a "request" to the external supply to change its output voltage (e.g., from a 5V baseline to 9V). After detecting that the voltage has changed, the controller then alters the transmitter's own internal operating frequency to precisely control the power level delivered to the receiving device. This dual-adjustment mechanism allows for granular power control without complex internal hardware (’970 Patent, Abstract; col. 4:1-14).
• Technical Importance: This method allows for the design of lower-cost, simpler transmitters that can intelligently leverage common, high-power external adapters to deliver a wide range of power levels efficiently, a key feature for standards like Qi2 (’970 Patent, col. 3:30-40).

Key Claims at a Glance

• The complaint asserts independent claim 1 and dependent claims 3-7, 11-12, 14, 16, 18-25 (Compl. ¶57).
• Independent Claim 1 of the ’970 Patent recites:
  • A power-supply interface for receiving a supply voltage from an external power supply.
  • A power conditioning system including an inverter.
  • A capacitor circuit and a transmission antenna.
  • At least one controller that executes a sequence:
    • Sends a request to the external power supply to change the voltage level.
    • Detects the voltage level has changed.
    • After detection, causes the configurable frequency of a drive signal to be changed.

III. The Accused Instrumentality

Product Identification

The "Accused Sariana Qi2 Wireless Chargers," which are sold under the Satechi brand name (Compl. ¶¶35-36). Specific models identified include the "Satechi Qi2 Trio Wireless Charging Pad" and the "Satechi Qi2 Wireless Car Charger," among others (Compl. ¶¶23, 25, 27).

Functionality and Market Context

The accused products are accessories for mobile devices that wirelessly charge a device's battery in compliance with the Qi2 Specification of the Wireless Power Consortium ("WPC") (Compl. ¶35). The complaint provides a screenshot from the WPC's public database listing nine Satechi products as "Qi2 compliant" (Compl. ¶34, p. 8). The Qi2 standard, which builds upon Apple's MagSafe technology, is marketed as providing faster, more efficient charging and better interoperability. The complaint notes that some of the accused products are advertised as "best sellers" (Compl. ¶26).

IV. Analysis of Infringement Allegations

The complaint incorporates by reference claim chart exhibits that were not publicly filed. The infringement analysis is therefore based on the narrative allegations in the complaint.

'084 Patent Infringement Allegations

The complaint alleges that the Accused Sariana Qi2 Wireless Chargers directly infringe at least claim 1 of the ’084 Patent (Compl. ¶52). The infringement theory appears to be that the functionality required by the Qi2 standard inherently practices the claimed invention. A visual of one of the accused chargers shows a device designed for charging modern smartphones (Compl. ¶37, p. 9). The core allegation is that the chipset and circuitry within the accused chargers constitute the claimed "dynamic tuning controller" and associated components. This controller allegedly senses operating conditions (e.g., temperature, device presence, and alignment) and dynamically adjusts parameters like operating frequency and capacitance to optimize power transfer, thereby meeting the limitations of claim 1, including the use of a "bank of two or more capacitors" for tuning.

'970 Patent Infringement Allegations

The complaint alleges that the accused chargers directly infringe at least claim 1 of the ’970 Patent (Compl. ¶57). This infringement theory focuses on the products' ability to deliver higher power levels (e.g., 15W fast charging), a feature advertised on the product packaging (Compl. ¶38, p. 10) and in product listings (Compl. ¶23). The theory is that to achieve these higher power levels, the Satechi chargers perform the sequence recited in claim 1: they communicate with a compatible external power supply (e.g., a USB-PD adapter) to "request" a higher voltage, and upon detecting the voltage change, the charger's controller alters its internal operating frequency to deliver the correct power level to the device. The product's user brochure, which details its components, is also provided as evidence (Compl. ¶39, p. 10).

Identified Points of Contention

• Scope Questions: For the ’084 Patent, a key dispute may be whether the tuning circuitry in the accused chargers meets the specific limitation of "a capacitor circuit that comprises a bank of two or more capacitors" that is configured and controlled as the claim requires. For the ’970 Patent, a central question will be whether the communication between the charger and an external adapter constitutes a "request" sent by the charger, as opposed to a power mode negotiated through a different mechanism.
• Technical Questions: A primary evidentiary challenge for NuCurrent will be to demonstrate the internal operation of the accused chargers. For the ’084 Patent, this involves proving the existence and function of the specific capacitor bank. For the ’970 Patent, this requires showing the precise cause-and-effect sequence: a voltage change request, followed by detection of that change, followed by a responsive change in operating frequency.

V. Key Claim Terms for Construction

Term: "a capacitor circuit that comprises a bank of two or more capacitors" (’084 Patent, claim 1)

• Context and Importance: The infringement analysis for the ’084 Patent may hinge on this structural limitation. Practitioners may focus on this term because if the accused products achieve dynamic tuning using a single variable capacitor or a different circuit architecture, it could support a non-infringement argument.
• Intrinsic Evidence for Interpretation:
  • Evidence for a Broader Interpretation: The specification discusses dynamic tuning more generally, which could be argued to encompass various methods for altering capacitance.
  • Evidence for a Narrower Interpretation: The claim language is specific. The abstract explicitly mentions a capacitor circuit with "two or more capacitors." The specification further describes embodiments with "a plurality of selectable capacitors" that are selected by a controller, and Figure 8 depicts multiple distinct capacitors (CTXa, CTXb, etc.), suggesting the "bank" is a discrete set of components (’084 Patent, Abstract; col. 3:38-43; Fig. 8).

Term: "send, to the external power supply, a request" (’970 Patent, claim 1)

• Context and Importance: This term is critical because it defines the interaction that initiates the patented power-altering sequence. Practitioners may focus on this term because the nature of the communication protocol (e.g., USB-PD) will be scrutinized to determine if the charger is the active "requestor" or if it is merely responding to options presented by the power supply.
• Intrinsic Evidence for Interpretation:
  • Evidence for a Broader Interpretation: A party might argue that any signal that results in a voltage change from the external supply constitutes a "request."
  • Evidence for a Narrower Interpretation: The specification explicitly mentions compatibility with standardized power supplies like "USB-C power supplies, USB-PD (USB Power Delivery) power supplies," which have defined protocols for power negotiation. This context suggests "request" refers to a specific, machine-readable command sent from the transmitter to the external supply as part of such a protocol (’970 Patent, col. 3:30-40).

VI. Other Allegations

Indirect Infringement

While not pleaded as a separate count, the complaint alleges facts that may support a claim for induced infringement. It notes that Defendant's product packaging includes a brochure that instructs on the use of the chargers, which could be argued to encourage infringing use by consumers (Compl. ¶39).

Willful Infringement

The complaint includes a count for willful infringement, alleging that Sariana had knowledge of the patents-in-suit and their relevance to Qi2 products since at least April 30, 2024, based on "no fewer than three notices of infringement" (Compl. ¶¶41, 49, 60-61). The complaint alleges Sariana's refusal to respond or negotiate a license constitutes "egregious misconduct" and "classic hold-out behavior" (Compl. ¶¶49, 61).

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

• A key evidentiary question will be one of structural and functional mapping: Can NuCurrent demonstrate through reverse engineering or discovery that the internal hardware and software logic of Satechi’s Qi2 chargers practice the specific structures and sequences recited in the asserted claims, particularly the "bank of two or more capacitors" (’084 Patent) and the "request-detect-change" sequence (’970 Patent)?
• A central legal and commercial issue will be the implications of standardization: Given NuCurrent’s allegation that the patents are "standard-essential" for Qi2 and that it offered a RAND license, the case will likely involve complex arguments regarding the scope of any licensing obligation, the reasonableness of the offered terms, and whether Sariana’s alleged "hold-out" behavior negates any defenses it might raise related to the patents' SEP status.
• A core issue will be one of causation: For the ’970 Patent, the dispute may turn on whether the accused charger’s change in operating frequency is a direct and intended consequence of its controller first detecting a voltage change from the external supply, or if these two events are merely correlated but not causally linked in the manner required by the claim.