Cobblestone Wireless LLC v. Motorola Mobility LLC

I. Executive Summary and Procedural Information

• Parties & Counsel:
  • Plaintiff: Cobblestone Wireless, LLC (Texas)
  • Defendant: Motorola Mobility LLC (Delaware)
  • Plaintiff’s Counsel: Russ August & Kabat
• Case Identification: 1:24-cv-08726, N.D. Ill., 09/20/2024
• Venue Allegations: Plaintiff alleges venue is proper because Defendant resides in the district, has a regular and established place of business in the district, and has committed alleged acts of infringement there.
• Core Dispute: Plaintiff alleges that Defendant’s cellular user equipment, such as the Motorola Edge 50 Ultra, infringes patents related to user-focused signal transmission (beamforming) and multi-frequency communications (carrier aggregation).
• Technical Context: The technologies at issue are foundational to modern high-speed wireless communication standards like 5G, enabling efficient data delivery and increased bandwidth.
• Key Procedural History: The complaint does not reference any prior litigation, inter partes review (IPR) proceedings, or licensing history related to the patents-in-suit.

Case Timeline

Date	Event
2008-01-23	’802 Patent Priority Date (Application Filing)
2011-04-12	’802 Patent Issue Date
2011-07-28	’347 Patent Priority Date (PCT Filing)
2014-11-18	’347 Patent Issue Date
2024-09-20	Complaint Filing Date

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

U.S. Patent No. 8,891,347: “User-Focusing Technique for Wireless Communication Systems,” issued November 18, 2014

The Invention Explained

• Problem Addressed: The patent describes challenges in wireless networks, including high capacity demands in "hot-spots" and interference. It notes that conventional equalization techniques place a computational burden on the receiver to correct signal distortions that arise during transmission (’347 Patent, col. 1:7-41).
• The Patented Solution: The invention proposes a method where the transmitter pre-distorts a signal based on channel characteristics fed back from the receiver. This pre-distortion is calculated so that the various multipath signal components arrive at the receiver's location in-phase and combine constructively, creating a signal "focus" at the user and shifting the burden of equalization from the receiver to the transmitter (’347 Patent, Abstract; col. 2:1-9).
• Technical Importance: This technique aims to improve signal quality and reduce interference by concentrating transmission energy at the intended user, potentially improving performance without requiring modifications to existing receiver hardware (’347 Patent, col. 8:56-65).

Key Claims at a Glance

• The complaint asserts independent Claim 1 (Compl. ¶10).
• Essential elements of Claim 1 (a method) include:
  • Transmitting a first signal from a transmitter to a receiver.
  • Receiving the first signal at the receiver.
  • Performing a channel estimation at the receiver to obtain path parameter information.
  • Sending the channel estimation from the receiver back to the transmitter.
  • Predistorting a second signal at the transmitter in the time, frequency, and spatial domains based on the channel estimation.
  • Transmitting the predistorted signal from the transmitter to the receiver.
  • Receiving the predistorted signal at the receiver.

U.S. Patent No. 7,924,802: “Wireless Communication Systems and Methods,” issued April 12, 2011

The Invention Explained

• Problem Addressed: The patent notes that wireless systems are often limited by the amount of data that can be transmitted around a single center frequency and by regulatory power limits, which can constrain reliability, range, and throughput (’802 Patent, col. 1:12-56).
• The Patented Solution: The invention discloses a method and system for simultaneously transmitting information over two or more distinct frequency ranges from a single transmitter, potentially using a single power amplifier. This allows for sending different data streams to increase throughput or sending the same data to improve reliability through frequency diversity (’802 Patent, Abstract; col. 6:57-63; Fig. 2).
• Technical Importance: The described method is an early articulation of the concept of carrier aggregation, a technology that became a core component of later cellular standards (e.g., LTE-Advanced, 5G) for increasing peak data rates.

Key Claims at a Glance

• The complaint asserts independent Claim 1 (Compl. ¶18).
• Essential elements of Claim 1 (a method) include:
  • Transmitting first information across a first frequency range using a wireless transmitter, the range having a first center frequency.
  • Simultaneously transmitting second information across a second frequency range using the same wireless transmitter, where the second range has a center frequency greater than the first.

III. The Accused Instrumentality

Product Identification

The complaint identifies "cellular user equipment (UE)," with the "Motorola's Edge 50 Ultra" cited as a non-limiting example (Compl. ¶¶10, 18).

Functionality and Market Context

The accused functionality relates to standard-compliant features of the devices. Specifically, the complaint alleges that the products' support for "3GPP 5G NR beamforming" infringes the ’347 Patent and their support for "3GPP carrier aggregation" infringes the ’802 Patent (Compl. ¶¶10, 18). These are high-end consumer smartphones whose market position relies on performance enabled by such 5G technologies.

IV. Analysis of Infringement Allegations

The complaint states that claim charts are attached as Exhibits 2 and 4, but these exhibits were not included with the filed complaint document (Compl. ¶¶13, 21). Accordingly, the infringement allegations are summarized below in prose based on the complaint's narrative. No probative visual evidence provided in complaint.

’347 Patent Infringement Allegations

The complaint alleges that the accused devices directly infringe Claim 1. The theory suggests that in a 5G network, the accused UE receives reference signals from a base station, performs a channel estimation, and reports this information back. The base station then uses this feedback to perform beamforming—a technique to focus transmitted energy—which the complaint equates to the claimed "predistorting" step. The UE then receives this predistorted/beamformed signal (Compl. ¶¶10, 13). A potential point of contention is that the asserted method claim includes steps performed by both the transmitter (base station) and the receiver (the accused UE), raising the question of whether a single party, Motorola, can be liable for direct infringement based on its making, using, or selling of the UE alone.

’802 Patent Infringement Allegations

The complaint alleges that the accused devices directly infringe Claim 1 by operating in a mode that uses carrier aggregation. This feature allows the UE to receive data simultaneously from a base station across multiple, distinct frequency bands to increase data throughput (Compl. ¶¶18, 21). The core of this allegation is that this standardized functionality maps directly onto the patent's claims for simultaneous transmission across different frequency ranges. A potential legal question arises from accusing a UE (a receiver) of directly infringing a method claim for "transmitting," an act primarily performed by the network's base station.

V. Key Claim Terms for Construction

’347 Patent, Claim 1: "predistorting a second signal at the transmitter"

• Context and Importance: The definition of this term is central, as the infringement case depends on whether the standardized beamforming/precoding techniques in 5G NR fall within its scope. Practitioners may focus on this term because the defense will likely argue that 5G precoding is a distinct, non-infringing technology.
• Intrinsic Evidence for a Broader Interpretation: The specification describes the goal of pre-distortion as causing transmitted signals to be "aligned in phases" so they can be "added constructively" at the receiver (’347 Patent, col. 2:27-30). This purpose-driven language could support an interpretation covering any transmitter-side manipulation that achieves this coherent combination.
• Intrinsic Evidence for a Narrower Interpretation: The detailed description provides a specific mathematical implementation for generating the pre-distorted signal, involving complex conjugates of the antenna array responses for each propagation path (’347 Patent, col. 9:30-50). This could support a narrower construction limited to that specific algorithm or technically equivalent structures.

’802 Patent, Claim 1: "simultaneously transmitting"

• Context and Importance: The viability of the infringement claim hinges on whether the data transmission scheduling across multiple carriers in 3GPP carrier aggregation constitutes "simultaneously transmitting."
• Intrinsic Evidence for a Broader Interpretation: The patent discloses transmitting different OFDM symbols "during a first time slot across the first up-converted frequency range and a second symbol... during the first time slot across the second up-converted frequency range" (’802 Patent, col. 4:45-49). This suggests "simultaneously" can refer to events occurring within the same transmission time interval, not necessarily at the exact same instant.
• Intrinsic Evidence for a Narrower Interpretation: The patent also describes a system where two up-converted signals are "simply added together at the input of [the power amplifier]" (’802 Patent, col. 6:57-60; Fig. 2). This might be argued to imply a stricter form of simultaneity, where signals are continuously combined and transmitted, potentially distinguishing it from the discrete, scheduled nature of 5G transmissions.

VI. Other Allegations

Indirect Infringement

The complaint pleads both induced and contributory infringement for both patents. Inducement is alleged based on Motorola providing user manuals and instructions that encourage use of the infringing functionalities, with knowledge of the patents alleged to exist at least from the service of the complaint (Compl. ¶¶11, 19). Contributory infringement is alleged on the basis that the accused devices are especially adapted to infringe and are not staple articles of commerce suitable for substantial non-infringing use (Compl. ¶¶12, 20).

Willful Infringement

While the word "willful" is not used in the infringement counts, the complaint alleges knowing and intentional inducement based on post-suit knowledge of the patents (Compl. ¶¶11, 19). The prayer for relief requests a finding that the case is "exceptional" under 35 U.S.C. § 285, a remedy often tied to findings of willful infringement (Compl., Prayer for Relief ¶E).

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

1. Direct Infringement by a Single Actor: A central issue will be whether Plaintiff can prove direct infringement of the asserted method claims. Both patents claim methods involving steps performed by a transmitter (base station) and a receiver (UE). The complaint accuses Motorola, the UE manufacturer, of direct infringement, which will require showing that Motorola itself performs or controls all claimed steps, presenting a potential divided infringement challenge.

2. Claim Scope vs. Industry Standard: The case will likely turn on claim construction. A key question for the court will be one of definitional scope: are the terms "predistorting" from the ’347 Patent and "simultaneously transmitting" from the ’802 Patent broad enough to encompass the specific, complex, and standardized implementations of 5G NR beamforming and carrier aggregation?

3. Evidentiary Sufficiency: The infringement contentions in the complaint are made at a high level, identifying accused standards without detailing the precise technical operations or providing the referenced claim chart exhibits. A key evidentiary question will be whether the technical operation of the accused devices, once detailed in discovery, actually meets each limitation of the asserted claims.