DCT
2:25-cv-00837
Empire Technology Development LLC v. Lenovo Group Ltd
Key Events
Complaint
I. Executive Summary and Procedural Information
- Parties & Counsel:
- Plaintiff: Empire Technology Development LLC (Delaware)
- Defendant: Lenovo Group Limited, et al. (Hong Kong / People's Republic of China)
- Plaintiff’s Counsel: Capshaw DeRieux, LLP; Milbank LLP
- Case Identification: 2:25-cv-00837, E.D. Tex., 08/21/2025
- Venue Allegations: Plaintiff alleges venue is proper because Defendants, as foreign corporations, may be sued in any judicial district, and because Defendants transact business and have committed acts of infringement in the Eastern District of Texas through authorized sellers and sales representatives.
- Core Dispute: Plaintiff alleges that Defendant’s 5G-compatible laptops, tablets, and smartphones infringe patents related to adaptive power control for wireless transmitters and methods for improving signal decoding in wireless communications.
- Technical Context: The technologies at issue concern methods for improving the energy efficiency and data-rate reliability of mobile devices operating on modern cellular networks like 5G.
- Key Procedural History: The complaint alleges the patents-in-suit originated from research at the University of Texas and are exclusively licensed to the Plaintiff. It also alleges that Defendant has been aware of the patents since at least May 2019 as a result of communications regarding a potential sale or license. The complaint notes that U.S. Patent No. 8,798,120 is the subject of a pending Inter Partes Review proceeding, IPR2024-00896.
Case Timeline
| Date | Event |
|---|---|
| 2009-03-18 | U.S. Patent No. 8,798,120 Priority Date |
| 2010-08-20 | U.S. Patent No. 8,565,331 Priority Date |
| 2013-10-22 | U.S. Patent No. 8,565,331 Issued |
| 2014-08-05 | U.S. Patent No. 8,798,120 Issued |
| 2019-05-31 | Plaintiff's counsel allegedly contacted Defendant with an offer to sell a portfolio including the patents-in-suit |
| 2020-01-06 | Defendant allegedly released the Flex 5G laptop, the first known infringing product |
| 2025-08-21 | Complaint Filed |
II. Technology and Patent(s)-in-Suit Analysis
U.S. Patent No. 8,798,120 - "METHODS AND COMMUNICATION SYSTEMS HAVING ADAPTIVE MODE SELECTION," issued Aug. 5, 2014
The Invention Explained
- Problem Addressed: In wireless communication, different transmission modes offer different trade-offs between data rate and power consumption (Compl. ¶33). For instance, Multiple-Input Multiple-Output (MIMO) can offer higher data rates but may consume more power than Single-Input Multiple-Output (SIMO) (’120 Patent, col. 2:16-24). The technical challenge is to operate a mobile device in a way that conserves energy without unduly sacrificing performance (’120 Patent, col. 2:40-44).
- The Patented Solution: The invention provides a method for adaptively selecting between MIMO and SIMO transmission modes. It does so by calculating transmission rates for each mode and selecting one based, at least in part, on the energy consumption associated with those rates, including the power consumed by the transceiver circuitry and the power consumed when the device is idle (’120 Patent, Abstract; col. 2:38-44). This allows the device to dynamically switch to the more energy-efficient mode for a given situation.
- Technical Importance: This adaptive approach to power management is aimed at extending the battery life of mobile devices, a critical factor for consumer electronics, while still allowing access to the high-performance benefits of technologies like 5G (Compl. ¶¶33-35).
Key Claims at a Glance
- The complaint asserts independent claim 25 (Compl. ¶55).
- Claim 25 recites a mobile station comprising:
- A first antenna and a second antenna;
- First and second circuitry coupled to the respective antennas to process signals for transmission;
- A controller coupled to the circuitry, configured to receive a control signal and select between a MIMO mode (both antennas transmit) and a SIMO mode (only one antenna transmits);
- Wherein the control signal is based, at least in part, on a power consumption of the first and second circuitry; and
- Wherein the control signal is based, at least in part, on an idle power consumption of the mobile station.
- The complaint does not explicitly reserve the right to assert dependent claims but notes its infringement examples are non-limiting (Compl. ¶59).
U.S. Patent No. 8,565,331 - "INSERTING AND DECODING REPLICATED DATA SYMBOLS IN WIRELESS COMMUNICATIONS," issued Oct. 22, 2013
The Invention Explained
- Problem Addressed: To reliably decode a signal, a receiver must estimate the properties of the communication channel (e.g., how the signal is affected by reflections and interference). This is typically done by inserting known, non-data "pilot symbols" into the transmission. However, the patent notes that the need to insert these pilot symbols "may adversely effect a data rate attainable in the communications system" because they take up bandwidth that could be used for actual data (’331 Patent, col. 2:3-6).
- The Patented Solution: The invention proposes using replicated data symbols to help with channel estimation. At least a portion of data from a first data stream is inserted (replicated) into a second data stream (’331 Patent, Abstract). Because the receiver knows this data is a copy, it can treat the replicated symbols like known pilot symbols to help decode the signal and generate an updated estimate of the channel matrix. This allows for improved channel estimation without dedicating as much of the transmission to non-data pilot symbols (’331 Patent, col. 4:4-14).
- Technical Importance: This technique seeks to improve the reliability and data rates of communications in complex multi-antenna systems, which is foundational to modern high-speed cellular networks (Compl. ¶38).
Key Claims at a Glance
- The complaint asserts independent claim 1 (Compl. ¶97).
- Claim 1 recites a method of decoding a signal, comprising the steps of:
- Receiving a pilot symbol over the communications channel;
- Estimating a channel matrix based, at least in part, on the pilot symbol;
- Receiving replicated data from multiple data streams transmitted over the communications channel;
- Decoding the replicated data using the estimated channel matrix;
- Generating an updated estimate of the channel matrix based, at least in part, on the replicated data; and
- Decoding subsequently received signals over the communications channel using the updated estimate of the channel matrix.
- The complaint does not explicitly reserve the right to assert dependent claims but notes its infringement examples are non-limiting (Compl. ¶101).
III. The Accused Instrumentality
Product Identification
The accused products are Lenovo’s 5G-compatible devices, including the Flex 5G laptop, various Edge, Moto, One, and Razr series smartphones, and Tab series tablets (Compl. ¶¶50-52). The complaint specifically identifies products incorporating Qualcomm Snapdragon modems (e.g., X55) and Qualcomm's "Smart Transmit" technology as infringing (Compl. ¶¶53, 72, 74).
Functionality and Market Context
The accused functionality relates to how these devices manage wireless transmissions in 5G networks (Compl. ¶¶53, 96). The complaint alleges that the "Smart Transmit" feature is a technology that "intelligently manage[s] transmit power" to optimize uplink speeds while complying with regulatory RF exposure limits (Compl. ¶¶76, 79). The complaint alleges these devices employ MIMO technology and use techniques such as spatial diversity to ensure reliable, high-speed communication (Compl. ¶¶73, 116). These features are presented as central to the performance and marketability of modern smartphones and mobile computers (Compl. ¶¶36, 39). The complaint provides an internal photograph from an FCC submission for the Flex 5G, identifying the locations of WWAN antennas and millimeter wave modules (Compl. ¶69, p. 24).
IV. Analysis of Infringement Allegations
’120 Patent Infringement Allegations
| Claim Element (from Independent Claim 25) | Alleged Infringing Functionality | Complaint Citation | Patent Citation |
|---|---|---|---|
| a first antenna and a second antenna | The accused products, such as the Flex 5G, include multiple Wireless WAN antennas for cellular communication. | ¶63 | col. 8:65-67 |
| first circuitry... second circuitry... configured to process signals for transmission by the... antenna | The accused products contain modules and circuitry, such as the Snapdragon X55 5G modem and RF front-end solutions, that process signals for the multiple antennas. | ¶69 | col. 8:1-5 |
| a controller... configured to... select between a multiple-input multiple-output (MIMO) mode... and a single-input multiple-output (SIMO) mode | The accused products are compatible with LTE Release 12, which defines distinct uplink transmission modes for SIMO (single transmit antenna) and MIMO (closed-loop spatial multiplexing). The complaint includes a table from a technical document illustrating these two modes (Compl. ¶73, p. 26). | ¶73 | col. 2:45-53 |
| wherein the control signal is based, at least in part, on a power consumption of the first and second circuitry | The "Smart Transmit" technology in the accused products is alleged to manage transmit power by allowing instantaneous power to exceed an average limit, which necessarily involves accounting for the power consumption of the transmission circuitry. A graph provided in the complaint shows transmit power fluctuating above and below an average power limit (Compl. ¶75, p. 27). | ¶74 | col. 7:59-62 |
| wherein the control signal is based, at least in part, on an idle power consumption of the mobile station | "Smart Transmit" allegedly engages in time-averaging of transmit power, which inherently accounts for periods of idle time when the transceiver is not transmitting at full power. An FCC report allegedly shows the device maintaining a "reserve level" of power to ensure the time-averaged transmission does not exceed limits. | ¶¶82-84 | col. 7:60-64 |
- Identified Points of Contention:
- Scope Questions: A central question may be whether the "Smart Transmit" feature, described as a technology for complying with RF exposure limits, constitutes a controller that "select[s]" between MIMO and SIMO modes for the purpose of energy efficiency as contemplated by the patent. The defense may argue its primary function is regulatory compliance, not power savings.
- Technical Questions: The analysis will likely focus on whether the control signal for "Smart Transmit" is truly "based... on" circuitry and idle power consumption as required by the claim. Does the alleged time-averaging function meet the "based on... idle power consumption" limitation, or does the claim require a more direct input or measurement of idle power in the selection logic?
’331 Patent Infringement Allegations
| Claim Element (from Independent Claim 1) | Alleged Infringing Functionality | Complaint Citation | Patent Citation |
|---|---|---|---|
| receiving a pilot symbol over the communications channel | The Snapdragon X55 modem in the accused products receives pilot signals (also called reference signals, like DM-RS) to estimate the wireless channel. The complaint includes a diagram illustrating the use of Demodulation Reference Signals (DMRS) for channel estimation in 5G (Compl. ¶111, p. 36). | ¶106 | col. 2:1-3 |
| estimating a channel matrix of the communications channel based, at least in part, on the pilot symbol | The modem uses the received pilot signals (DM-RS) to generate an initial estimate of the channel matrix, which is essential for supporting high data rates. | ¶109 | col. 2:63-65 |
| receiving replicated data from multiple data streams transmitted over the communications channel | The Snapdragon X55 modem allegedly employs spatial diversity, which is described as improving reliability by "sending the same data across different propagation, or spatial, paths." The complaint equates this to receiving "replicated data." | ¶¶114, 116 | col. 4:6-9 |
| decoding the replicated data using the estimated channel matrix | The modem decodes the received data, including the data sent via spatial diversity, using the channel estimate derived from pilot signals. | ¶118 | col. 1:65-67 |
| generating an updated estimate of the channel matrix based, at least in part, on the replicated data | The complaint alleges that data within a resource block, including replicated data, is used to "improve or update the channel estimate." | ¶123 | col. 3:1-3 |
| decoding subsequently received signals... using the updated estimate of the channel matrix | The modem uses the improved and updated channel estimate to decode all subsequent data received over the communications channel. | ¶127 | col. 1:65-67 |
- Identified Points of Contention:
- Scope Questions: The dispute may turn on the definition of "replicated data." Does the term, in the context of the patent, cover data transmitted identically across multiple streams for reliability (i.e., spatial diversity), or is it limited to data that is specifically inserted and used for the purpose of updating a channel estimate, as the patent's problem-solution statement suggests?
- Technical Questions: What evidence does the complaint provide that the accused devices actually use the data from spatial diversity streams to "generat[e] an updated estimate of the channel matrix"? The defense may argue that this data is used only for error correction or signal combining, not for re-calculating the channel matrix itself.
V. Key Claim Terms for Construction
For the ’120 Patent:
- The Term: "the control signal is based, at least in part, on..."
- Context and Importance: This phrase appears in the final two limitations of claim 25 and is central to connecting the accused "Smart Transmit" technology to the patent. The dispute will likely focus on how direct the relationship must be between the power consumption values (circuitry and idle) and the signal that selects between MIMO and SIMO modes.
- Intrinsic Evidence for Interpretation:
- Evidence for a Broader Interpretation: The phrase "at least in part" suggests that power consumption need not be the sole or even primary factor, allowing for other considerations. The detailed description states the selection may be based on an "energy consumption of the first and second transmission rates" (’120 Patent, col. 2:42-44), which could be interpreted broadly to include any system whose output is influenced by power usage.
- Evidence for a Narrower Interpretation: The abstract and summary focus on selecting a mode to be energy-efficient. The description of the energy-optimized rate calculation involves specific power variables like "Pdc,m" (power consumption of circuitry) and "Pidle" (idle power) (’120 Patent, col. 3:13; col. 4:45-50). A party could argue this implies that "based on" requires these factors to be explicit inputs into a decision-making algorithm, not just indirect consequences of a different function like RF exposure management.
For the ’331 Patent:
- The Term: "replicated data"
- Context and Importance: This term is the core of the invention. The infringement theory hinges on equating the practice of "spatial diversity" (sending the same data on different paths for reliability) with the patent's concept of "replicated data."
- Intrinsic Evidence for Interpretation:
- Evidence for a Broader Interpretation: Claim 1 itself does not specify the purpose for which the data is replicated, only that replicated data is received and then used to update the channel estimate. The claim language focuses on the sequence of steps, not the transmitter's intent. The specification describes replicating "at least a portion of data from one data stream" and inserting it into another, a process that is facially similar to spatial diversity (’331 Patent, col. 4:51-54).
- Evidence for a Narrower Interpretation: The patent consistently frames the invention as a way to use data symbols as pilot symbols to solve the problem of pilot signals reducing the data rate (’331 Patent, col. 2:3-6; col. 4:4-14). The summary states the disclosure relates to the "use of replicated data as a pilot symbol" (’331 Patent, col. 4:5-6). This suggests "replicated data" may be construed to mean data that is specifically designated and processed by the receiver as a pilot substitute for the express purpose of channel estimation, a function that may be distinct from merely combining identical data streams for diversity gain.
VI. Other Allegations
- Indirect Infringement: For both patents, the complaint alleges induced infringement under 35 U.S.C. § 271(b). It asserts that by manufacturing, selling, and providing instructions, product manuals, and technical support for the accused products, Defendants specifically intend for their customers to use the products in an infringing manner (Compl. ¶¶56, 98). It also alleges contributory infringement under § 271(c), stating the accused products are a material part of the invention, are not staple articles of commerce, and have no substantial non-infringing use (Compl. ¶¶57, 99).
- Willful Infringement: The complaint alleges that infringement has been willful because Defendant has known of the patents-in-suit and their relevance since at least May 2019, when Plaintiff's counsel allegedly contacted Defendant about a portfolio containing the patents (Compl. ¶¶86-89, 129-132). Despite this alleged pre-suit knowledge, Defendant allegedly continued its infringing activities.
VII. Analyst’s Conclusion: Key Questions for the Case
This case will likely depend on the resolution of fundamental questions of technical function and definitional scope. The key questions for the court appear to be:
- A core issue will be one of functional purpose: Does Lenovo's "Smart Transmit" technology, which is marketed as a system for RF exposure compliance, operate in a manner that meets the limitations of a claimed invention for adaptive, energy-efficient mode selection? Or is there a fundamental mismatch between the problem the accused technology solves and the problem the ’120 patent claims to solve?
- A second core issue will be one of definitional scope: Can the term "replicated data," taught in the ’331 patent as a substitute for pilot symbols to improve data rates, be construed to cover data sent across multiple paths for "spatial diversity," a technique primarily used to improve signal reliability?
- Finally, a key evidentiary question will be one of technical mechanism: Assuming spatial diversity can be "replicated data," does the complaint provide sufficient evidence that the accused Snapdragon modems actually use this redundant data to "generat[e] an updated estimate of the channel matrix," as required by Claim 1 of the ’331 patent, or is the data used for a different purpose, such as signal combining for error reduction?