DCT
4:25-cv-00820
USTA Technology LLC v. T-Mobile USA Inc
I. Executive Summary and Procedural Information
- Parties & Counsel:
- Plaintiff: USTA Technology, LLC (Delaware)
- Defendant: T-Mobile USA, Inc. (Delaware)
- Plaintiff’s Counsel: Devlin Law Firm LLC
- Case Identification: 4:25-cv-00820, E.D. Tex., 07/29/2025
- Venue Allegations: Plaintiff alleges venue is proper in the Eastern District of Texas because Defendant T-Mobile maintains regular and established places of business within the district, including numerous retail and corporate office locations.
- Core Dispute: Plaintiff alleges that Defendant’s 802.11ac-compliant networking products infringe a patent related to dynamic spectrum management in wireless networks.
- Technical Context: The lawsuit concerns technology for dynamic spectrum management, which enables wireless devices to opportunistically use licensed frequency bands by intelligently detecting and avoiding interference with incumbent users.
- Key Procedural History: The patent-in-suit, U.S. RE47,720, is a reissue of U.S. Patent No. 7,483,711. The complaint states the invention was developed to provide a practical implementation for spectrum sharing policies proposed by the FCC Spectrum Management Policy Task Force in 2002.
Case Timeline
| Date | Event |
|---|---|
| 2002-10-24 | '720 Patent Priority Date |
| 2013-12-01 | IEEE 802.11ac standard published (approximate date per complaint) |
| 2019-11-05 | '720 Patent Issue Date |
| 2025-07-29 | Complaint Filing Date |
II. Technology and Patent(s)-in-Suit Analysis
U.S. Patent No. RE47,720 - “Spectrum-Adaptive Networking”
The Invention Explained
- Problem Addressed: The patent addresses the increasing scarcity of available radio frequency spectrum and the difficulty of managing interference between a growing number of wireless devices. It specifically notes that while regulatory policies (such as those from the FCC) proposed allowing secondary devices to operate opportunistically below an "interference temperature" threshold, there was a need for the actual tools and methods to build networks that could comply with such rules (Compl. ¶¶ 17-19; ’720 Patent, col. 1:11-64).
- The Patented Solution: The patent describes a "receiver-centric" system where each receiving node in a network continuously senses the local spectrum to identify frequencies occupied by legacy users or other interference. Based on this real-time analysis, the receiver generates an "optimal waveform profile"—a set of instructions defining which frequencies are clear for use and at what power levels—and communicates this profile to neighboring nodes that wish to transmit to it. This allows for dynamic, adaptive use of shared spectrum while minimizing interference ('720 Patent, Abstract; col. 12:1-10, Fig. 14).
- Technical Importance: This approach provides a systematic method for implementing dynamic spectrum access, a key strategy for improving the efficiency of crowded frequency bands and enabling coexistence between different wireless systems (Compl. ¶22; ’720 Patent, col. 2:2-7).
Key Claims at a Glance
- The complaint asserts independent claim 19 (Compl. ¶44).
- Essential elements of independent claim 19 include:
- A first node receiving an instruction from a second node to avoid certain frequencies.
- The first node filtering a transmission signal to remove power at the avoided frequencies.
- The first node receiving compressed feedback from the second node and, separately, from a third node.
- The first node decompressing the feedback from both nodes.
- The first node generating one or more data structures based on the combined decompressed feedback.
- The first node simultaneously transmitting a first filtered signal to the second node and a second filtered signal to the third node, where the power for each transmission is based on the generated data structure(s).
- The complaint reserves the right to amend its infringement contentions, which may include the assertion of additional claims (Compl. ¶44).
III. The Accused Instrumentality
Product Identification
The complaint identifies the "Accused Instrumentalities" as a broad category of 802.11ac-compliant products, including specific examples such as the "T-Mobile 5G Gateway (G4AR & G4SE)," "Sagemcom Fast 5688W Gateway," "Inseego MiFi® X PRO 5G," and various other gateways, routers, hotspots, and access points made, used, or sold by T-Mobile (Compl. ¶41).
Functionality and Market Context
The core accused functionality is the implementation of the "wideband channel access features of the 802.11ac standard," which the complaint alleges includes the "very-high throughput ('VHT') beamforming protocols" (Compl. ¶¶ 39, 42). The complaint alleges that compliance with the 802.11ac standard requires devices to perform the method steps of the asserted claims (Compl. ¶39). T-Mobile is alleged to market these products for use in its "5G Home Internet service," encouraging customers to adopt it over conventional internet services (Compl. ¶45).
IV. Analysis of Infringement Allegations
No probative visual evidence provided in complaint.
The complaint alleges that devices supporting the 802.11ac standard necessarily practice the elements of claim 19 (Compl. ¶¶ 39, 43). The following chart summarizes the infringement theory based on the allegations.
RE47,720 Infringement Allegations
| Claim Element (from Independent Claim 19) - | Alleged Infringing Functionality - | Complaint Citation | Patent Citation |
|---|---|---|---|
| A method for managing interference in a radio communications network, comprising the steps of: receiving at a first node...an instruction transmitted from a second node...to avoid using a plurality of frequencies... | The Accused Instrumentalities are alleged to perform this step as part of their 802.11ac-compliant operation. - | ¶43 | col. 29:2-7 |
| filtering a transmission signal to remove power from the transmission signal at each frequency in the plurality of frequencies to be avoided; - | The Accused Instrumentalities are alleged to perform this step as part of their 802.11ac-compliant operation. - | ¶43 | col. 29:8-11 |
| separately from the receipt of the instruction, receiving a compressed first feedback from the second node that is based on a received power and one or more frequencies of a first signal transmitted from the first node to the second node; | The Accused Instrumentalities are alleged to perform this step as part of their 802.11ac-compliant operation. - | ¶43 | col. 29:13-18 |
| separately...receiving a compressed second feedback from a third node that is based on a received power and one or more frequencies of a second signal transmitted from the first node to the third node; | The Accused Instrumentalities are alleged to perform this step as part of their 802.11ac-compliant operation. - | ¶43 | col. 29:19-24 |
| decompressing the compressed first feedback...; decompressing the compressed second feedback...; - | The Accused Instrumentalities are alleged to perform this step as part of their 802.11ac-compliant operation. - | ¶43 | col. 29:25-28 |
| generating one or more data structures based on the decompressed first feedback and the decompressed second feedback; - | The Accused Instrumentalities are alleged to perform this step as part of their 802.11ac-compliant operation. - | ¶43 | col. 29:29-31 |
| wherein the filtered transmission signal is a filtered first transmission signal that is transmitted using a first frequency and an 802.11-based...protocol...using a first power that is based on at least one of the one or more data structures; | The Accused Instrumentalities are alleged to perform this step as part of their 802.11ac-compliant operation. - | ¶43 | col. 29:32-37 |
| and further comprising: transmitting, using a second frequency and the 802.11-based...protocol, a filtered second transmission signal, simultaneously with the filtered first transmission signal, to the third node, using a second power that is based on at least one of the one or more data structures. | The Accused Instrumentalities are alleged to perform this step as part of their 802.11ac-compliant operation. - | ¶43 | col. 29:38-39; col. 30:1-6 |
Identified Points of Contention
- Scope Questions: The complaint’s central theory is that compliance with the 802.11ac standard is sufficient to prove infringement (Compl. ¶39). This raises the question of whether the 802.11ac standard mandates the performance of every element of claim 19, or if there are alternative, non-infringing ways to comply with the standard.
- Technical Questions: Claim 19 requires a specific choreography involving three distinct nodes, the generation of data structures from feedback received from two different nodes, and the use of those structures to control simultaneous transmissions. What evidence does the complaint provide that the Accused Instrumentalities perform this complex, multi-step process, particularly the generation of a single data structure from two independent feedback sources to control two separate transmissions?
V. Key Claim Terms for Construction
The Term: "compressed first feedback from the second node that is based on a received power and one or more frequencies"
- Context and Importance: This term defines the nature of the information that a node must receive to manage interference. The infringement analysis will depend on whether standard 802.11ac channel state information or other feedback mechanisms meet this definition, or if the claim requires a more specific type of data packet containing explicit power-and-frequency measurements. Practitioners may focus on this term because the defendant could argue that standard protocol messages do not contain the specific information required by the claim.
- Intrinsic Evidence for Interpretation:
- Evidence for a Broader Interpretation: The patent discusses closed-loop power control in general terms, where "each receiver sends to other nodes in the network a request to adjust...its transmission power level" to ensure signals arrive at the same power level ( ’720 Patent, col. 3:38-44). This might support a functional interpretation covering any feedback that achieves this goal.
- Evidence for a Narrower Interpretation: The specification describes a specific process where a receiving node performs detailed spectral analysis and generates an "optimal waveform profile" that is then transmitted to neighbors ('720 Patent, col. 12:4-10). This could support an argument that the "feedback" must be this specific, calculated profile, not a more generic status message.
The Term: "generating one or more data structures based on the decompressed first feedback and the decompressed second feedback"
- Context and Importance: This limitation is the computational core of the claimed method. The power for two simultaneous, separate transmissions is dictated by these data structures. The case may turn on whether this requires a novel computation combining feedback from two nodes, a function a defendant might argue is not performed by standard 802.11ac chipsets.
- Intrinsic Evidence for Interpretation:
- Evidence for a Broader Interpretation: The term "data structure" is inherently broad and could refer to any organized block of data in memory used for processing.
- Evidence for a Narrower Interpretation: The patent’s Figure 14 depicts a specific "waveform profile generator" (1435) and "signal data processor" (1430) that perform this function ('720 Patent, Fig. 14). A party could argue that the term "data structures" should be construed in the context of the specific inputs and outputs of these disclosed components, limiting its scope to more than just a generic data object.
VI. Other Allegations
- Indirect Infringement: The complaint alleges facts that may support a claim for induced infringement. It states that T-Mobile "encourages customers and other end-users to utilize its 5G Home Internet service" and provides services for "setting up, testing, operating, maintaining, and/or upgrading" these networks, which allegedly instructs or encourages the performance of the claimed method (Compl. ¶¶ 45, 47).
- Willful Infringement: The complaint does not explicitly allege willful infringement. However, it requests that the court declare the case "exceptional under 35 U.S.C. § 285" and award attorneys' fees (Prayer for Relief, C). The complaint does not plead facts showing pre-suit knowledge of the patent by the defendant.
VII. Analyst’s Conclusion: Key Questions for the Case
- A core issue will be one of standards essentiality: Is the complex multi-node method of Claim 19 a mandatory feature of the IEEE 802.11ac standard as the complaint alleges, or are there non-infringing implementations of the standard? The outcome will likely depend on a detailed analysis of the standard's specifications versus the claim's specific limitations.
- A key evidentiary question will be one of technical proof: Beyond the argument from standards, can the Plaintiff demonstrate through technical evidence (e.g., packet captures, source code analysis, or reverse engineering) that the accused T-Mobile products actually perform the claimed three-node communication, including receiving compressed feedback from two nodes, generating data structures from both, and using them to control simultaneous transmissions?
- The dispute may also hinge on claim construction: Will the court interpret terms like "compressed first feedback" and "data structures" broadly to cover functionalities present in the 802.11ac protocol, or will it adopt a narrower construction tied to the specific "optimal waveform profile" generation embodiments described in the patent's specification?