DCT

2:25-cv-07967

Entropic Communications LLC v. Comcast Corp

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I. Executive Summary and Procedural Information

  • Parties & Counsel:
  • Case Identification: 2:25-cv-07967, C.D. Cal., 08/23/2025
  • Venue Allegations: Plaintiff alleges venue is proper because Defendants operate regular and established places of business in the district, such as Xfinity retail stores, and have committed acts of infringement within the district by making, using, selling, and offering for sale the accused products and services.
  • Core Dispute: Plaintiff alleges that Defendant’s MoCA-compliant Xfinity cable television equipment and services infringe twelve patents related to networking over existing in-home coaxial cables.
  • Technical Context: The technology, standardized as Multimedia over Coax Alliance (MoCA), enables high-speed, in-home data networking using existing coaxial television cables, which is critical for services like whole-home DVR without requiring costly new Ethernet wiring.
  • Key Procedural History: The complaint states that this case is being filed to preserve rights following a prior, similar lawsuit filed by Entropic against Comcast in the same district on February 10, 2023 (the “First Case”). Entropic asserts that in the First Case, a court found seven of the currently asserted patents to be directed to patent-ineligible subject matter or invalid as indefinite. Additionally, the Patent Trial and Appeal Board (PTAB) found claims of two other asserted patents to be unpatentable. Entropic states it is re-asserting these nine patents in the present case to preserve its rights pending appeal of those prior adverse decisions.

Case Timeline

Date Event
2001-05-04 U.S. Patent No. 7,594,249 Priority Date
2001-08-30 U.S. Patent No. 7,295,518 Priority Date
2001-08-30 U.S. Patent No. 7,889,759 Priority Date
2004-12-02 U.S. Patent No. 8,085,802 Priority Date
2004-12-02 U.S. Patent No. 8,631,450 Priority Date
2004-12-02 U.S. Patent No. 10,257,566 Priority Date
2004-12-02 U.S. Patent No. 8,621,539 Priority Date
2007-02-06 U.S. Patent No. 9,838,213 Priority Date
2007-02-06 U.S. Patent No. 10,432,422 Priority Date
2007-05-09 U.S. Patent No. 8,228,910 Priority Date
2008-10-16 U.S. Patent No. 8,320,566 Priority Date
2008-10-16 U.S. Patent No. 8,363,681 Priority Date
2007-11-13 U.S. Patent No. 7,295,518 Issue Date
2009-09-22 U.S. Patent No. 7,594,249 Issue Date
2011-02-15 U.S. Patent No. 7,889,759 Issue Date
2011-12-27 U.S. Patent No. 8,085,802 Issue Date
2012-07-24 U.S. Patent No. 8,228,910 Issue Date
2012-11-27 U.S. Patent No. 8,320,566 Issue Date
2013-01-29 U.S. Patent No. 8,363,681 Issue Date
2013-12-31 U.S. Patent No. 8,621,539 Issue Date
2014-01-14 U.S. Patent No. 8,631,450 Issue Date
2017-12-05 U.S. Patent No. 9,838,213 Issue Date
2019-04-09 U.S. Patent No. 10,257,566 Issue Date
2019-10-01 U.S. Patent No. 10,432,422 Issue Date
2022-08-09 Plaintiff sends communication to Defendant regarding licensing (Compl. ¶39)
2023-02-10 Plaintiff files the First Case against Defendant (Compl. ¶31)
2025-08-22 Alleged termination date of Vendor Service Agreement (Compl. ¶57)
2025-08-23 Complaint Filing Date (Compl. p. 1)

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

U.S. Patent No. 7,295,518 - “Broadband Network for Coaxial Cable Using Multi-Carrier Modulation”

  • Patent Identification: U.S. Patent No. 7,295,518, titled “Broadband Network for Coaxial Cable Using Multi-Carrier Modulation,” issued November 13, 2007 (’518 Patent).

The Invention Explained

  • Problem Addressed: The patent addresses the difficulty of creating a local area network (LAN) using existing in-home coaxial cable wiring, which contains signal splitters that isolate different rooms and cause signal impairments like multipath reflections (US 7,295,518 B1, col. 2:30-41).
  • The Patented Solution: The invention uses a multi-carrier modulation scheme, such as Orthogonal Frequency Division Multiplexing (OFDM), to overcome these impairments. It proposes sending "probe messages" between devices to characterize the unique communication channel path and then using "bit loading" to optimize the data transmission by assigning higher-order modulation schemes to frequency carriers with a better signal-to-noise ratio (’518 Patent, Abstract; col. 4:51-64).
  • Technical Importance: This adaptive modulation technique enabled reliable, high-speed data communication over the physically inconsistent and "hostile" coaxial wiring environment typically found in homes (Compl. ¶79).

Key Claims at a Glance

  • The complaint asserts at least independent claim 1 (Compl. ¶134, ¶138).
  • Claim 1 is a method for communicating data between devices on a coaxial network, comprising the essential elements of:
    • Transmitting a probe message from a first device to a second device.
    • Receiving the probe message at the second device.
    • Determining a channel characteristic of the channel path based on the probe message.
    • Determining a bit loading for the channel path based on the channel characteristic.
    • Transmitting a response message from the second device back to the first, the response including the bit loading.
    • Receiving the response message at the first device.
    • Transmitting a data message from the first device to the second device using the bit loading.
  • The complaint does not explicitly reserve the right to assert dependent claims for this patent.

U.S. Patent No. 7,594,249 - “Network Interface Device and Broadband Local Area Network Using Coaxial Cable”

  • Patent Identification: U.S. Patent No. 7,594,249, titled “Network Interface Device and Broadband Local Area Network Using Coaxial Cable,” issued September 22, 2009 (’249 Patent).

The Invention Explained

  • Problem Addressed: The patent describes how signal splitters in typical home coaxial wiring are designed to prevent signals from traveling between different output ports ("port-to-port isolation"), which obstructs the creation of a LAN where devices in different rooms need to communicate directly (US 7,594,249 B2, col. 1:44-51).
  • The Patented Solution: The invention introduces a frequency-selective network interface device, placed at the building's point of entry (POE), that is designed to reflect network signals sent "upstream" from a device back "downstream" into the home wiring. This reflection creates a communication path allowing a signal from one device to reach all other devices on the network, bypassing the isolation of the splitters (US 7,594,249 B2, col. 2:13-22).
  • Technical Importance: This provided a passive, physical-layer solution for enabling LAN communications over existing coax topologies without requiring active signal routing or modification of the in-home wiring (Compl. ¶160).

Key Claims at a Glance

  • The complaint asserts at least independent claim 10 (Compl. ¶166, ¶170).
  • Claim 10 is a broadband local area network comprising the essential elements of:
    • A filter located at the point of entry of building wiring that rejects network signals such that the signals are reflected back into the wiring.
    • A plurality of terminal devices connected to the wiring branches.
    • Each terminal device being capable of communicating with others via the reflected signal path.
    • The terminal devices performing equalization on the received signal to restore a flat frequency response and overcome channel impairments.
  • The complaint does not explicitly reserve the right to assert dependent claims for this patent.

Multi-Patent Capsules

  • U.S. Patent No. 7,889,759 (’759 Patent) - “Broadband Cable Network Utilizing Common Bit-Loading”

    • Technology Synopsis: The patent describes a method for establishing a common modulation scheme for communications between multiple nodes in a broadband cable network. A transmitting node sends a probe signal, receives response signals from multiple receiving nodes that each include a bit-loaded modulation scheme, and then determines a common scheme based on comparing the different responses (’759 Patent, Abstract; Compl. ¶192).
    • Asserted Claims: At least independent claim 2 is asserted (Compl. ¶198, ¶202).
    • Accused Features: The Accused MoCA Instrumentalities, which are alleged to be compliant with MoCA standards 1.0, 1.1, and/or 2.0 (Compl. ¶201).

  • U.S. Patent No. 8,085,802 (’802 Patent) - “Multimedia over Coaxial Cable Access Protocol”

    • Technology Synopsis: The technology is directed to establishing and periodically adapting modulation and transmission parameters for communication between pairs of devices on a coaxial cable network. The aim is to optimize the communication channel between each pair of devices (’802 Patent, col. 4:7-24; Compl. ¶226).
    • Asserted Claims: At least independent claim 3 is asserted (Compl. ¶230, ¶234).
    • Accused Features: The Accused MoCA Instrumentalities, alleged to comply with MoCA standards 1.0, 1.1, and/or 2.0 (Compl. ¶233).

  • U.S. Patent No. 9,838,213 (’213 Patent) - “Parameterized Quality of Service Architecture in a Network”

    • Technology Synopsis: The invention relates to managing network resources to provide guaranteed quality of service (QoS) for multimedia data streams (e.g., video, audio) over on-premises coaxial networks. It describes techniques for allocating resources to ensure reliable delivery for interactive and streaming services (’213 Patent, col. 3:46-53; Compl. ¶355).
    • Asserted Claims: At least independent claims 1, 13, and 23 are asserted (Compl. ¶359).
    • Accused Features: The Accused MoCA Instrumentalities, alleged to comply with MoCA standards 1.1 and/or 2.0 (Compl. ¶362).

  • U.S. Patent No. 10,432,422 (’422 Patent) - “Parameterized Quality of Service Architecture in a Network”

    • Technology Synopsis: This patent is also directed to low-cost and high-speed management of network resources to ensure guaranteed quality of service for multimedia data flows in a MoCA network. It involves techniques for allocating resources for specific service flows between devices (’422 Patent, col. 3:53-60; Compl. ¶387).
    • Asserted Claims: At least independent claims 1, 5, and 12-17 are asserted (Compl. ¶391).
    • Accused Features: The Accused MoCA Instrumentalities, alleged to comply with MoCA standards 1.1 and/or 2.0 (Compl. ¶394).

  • U.S. Patent No. 8,631,450 (’450 Patent) - “Broadband Local Area Network”

    • Technology Synopsis: The patent addresses techniques for determining a common modulation scheme for communications between nodes in a MoCA network. It describes establishing communication by activating a first modem, which then admits other modems to the network and establishes transmission parameters (’450 Patent, col. 4:12-28; Compl. ¶257).
    • Asserted Claims: At least independent claims 1, 8, 27, 29, and 34 are asserted (Compl. ¶263).
    • Accused Features: The Accused MoCA Instrumentalities, alleged to comply with MoCA standards 1.0, 1.1, and/or 2.0 (Compl. ¶266).

  • U.S. Patent No. 8,621,539 (’539 Patent) - “Physical Layer Transmitter for use in a Broadband Local Area Network”

    • Technology Synopsis: The invention relates to a physical layer transmitter for performing RF, analog, and digital processing for transmitting messages between devices in a broadband cable network. The technology is directed at techniques for monitoring and maintaining modulation profiles used in the MoCA network (’539 Patent, col. 4:37-48; Compl. ¶323).
    • Asserted Claims: At least independent claim 1 is asserted (Compl. ¶327, ¶331).
    • Accused Features: The Accused MoCA Instrumentalities, alleged to comply with MoCA standards 1.0, 1.1, and/or 2.0 (Compl. ¶330).

  • U.S. Patent No. 8,320,566 (’0,566 Patent) - “Method and Apparatus for Performing Constellation Scrambling in a Multimedia Home Network”

    • Technology Synopsis: The patent describes allowing multiple transmitting devices to transmit under an orthogonal frequency divisional multiple access (OFDMA) mode to a single receiving device. It covers techniques for assigning communication resources to nodes in the MoCA network (’0,566 Patent, Abstract; Compl. ¶450).
    • Asserted Claims: At least independent claims 1, 7, 13, and 16 are asserted (Compl. ¶456).
    • Accused Features: The Accused MoCA Instrumentalities, alleged to comply with MoCA standard 2.0 (Compl. ¶459).

  • U.S. Patent No. 10,257,566 (’7,566 Patent) - “Broadband Local Area Network”

    • Technology Synopsis: This patent relates to establishing and periodically adapting modulation and other transmission parameters between pairs of devices on a coaxial network. It is directed to techniques for controlling the admission of nodes into the MoCA network (’7,566 Patent, col. 4:23-39; Compl. ¶291).
    • Asserted Claims: At least independent claims 1, 11, and 19 are asserted (Compl. ¶295).
    • Accused Features: The Accused MoCA Instrumentalities, alleged to comply with MoCA standards 1.0, 1.1, and/or 2.0 (Compl. ¶298).

  • U.S. Patent No. 8,228,910 (’910 Patent) - “Aggregating Network Packets for Transmission to a Destination Node”

    • Technology Synopsis: The invention describes a method for aggregating multiple data packets directed to a common destination into a single larger packet. This technique is intended to reduce overhead by eliminating redundant information such as interframe gaps and extra headers (’910 Patent, col. 1:66-col. 2:3; Compl. ¶419).
    • Asserted Claims: At least independent claim 3 is asserted (Compl. ¶423, ¶427).
    • Accused Features: The Accused MoCA Instrumentalities, alleged to comply with MoCA standards 1.1 or 2.0 (Compl. ¶426).

  • U.S. Patent No. 8,363,681 (’681 Patent) - “Method and Apparatus for Using Ranging Measurements in a Multimedia Home Network”

    • Technology Synopsis: This patent is directed to improving local clock time synchronization between multiple nodes in a communication network. It describes using ranging measurements to estimate propagation delay between nodes, which is then used to synchronize their local clocks (’681 Patent, Abstract; Compl. ¶484).
    • Asserted Claims: At least independent claims 1, 11, 21, and 31 are asserted (Compl. ¶488).
    • Accused Features: The Accused MoCA Instrumentalities, alleged to comply with MoCA standard 2.0 (Compl. ¶491).

III. The Accused Instrumentality

Product Identification

  • The complaint identifies the accused products as "Accused MoCA Instrumentalities" and the associated services as "Accused Services" (Compl. ¶1). Specific examples of instrumentalities include Comcast’s gateway devices (e.g., XG1-A, XG1v3, XG1v4, XG2v2) and client devices (e.g., Arris DCX3200, Pace PR150BNM) (Compl. ¶86).

Functionality and Market Context

  • The Accused MoCA Instrumentalities are components deployed by Comcast to provide a whole-premises DVR network and other services over a customer's existing in-home coaxial cable network (Compl. ¶86). These devices operate as nodes compliant with MoCA standards 1.0, 1.1, and/or 2.0, forming a local area network that connects devices like routers, IP clients, and set-top boxes (Compl. ¶88). An exemplary network topology provided in the complaint shows a router connecting various IP clients over a MoCA network (Compl. p. 17, Figure 5).
  • The complaint alleges that MoCA technology is the "backbone of data and entertainment services for tens of millions of customers" (Compl. ¶4). It further cites a 2010 statement from a Comcast senior director indicating that "all new products will have MoCA embedded into them," suggesting the technology's strategic importance to Defendant's offerings (Compl. ¶93).

IV. Analysis of Infringement Allegations

The complaint alleges that any product or system operating in a MoCA network compliant with the charted provisions of MoCA 1.0, 1.1, and/or 2.0 necessarily infringes the asserted claims (Compl. ¶134, ¶166). The infringement allegations are premised on the Accused MoCA Instrumentalities being compliant with these MoCA standards and being used by Comcast and its customers to provide the Accused Services.

U.S. Patent No. 7,295,518 Infringement Allegations

Claim Element (from Independent Claim 1) Alleged Infringing Functionality Complaint Citation Patent Citation
A method for communicating data between a first device and a second device over a coaxial cable network... Comcast deploys and uses the Accused MoCA Instrumentalities to provide the Accused Services over an on-premises coaxial cable network. ¶131, ¶138 col. 4:51-53
transmitting a probe message from a first device to a second device over the coaxial cable network; The Accused MoCA Instrumentalities, operating in a MoCA-compliant manner, transmit probe messages between nodes to characterize the communication channel. ¶129, ¶137 col. 8:38-42
determining a channel characteristic of the channel path based on the probe message; The Accused MoCA Instrumentalities receive and analyze probe messages to determine the channel characteristics as part of MoCA-compliant network operation. ¶129, ¶137 col. 4:56-58
determining a bit loading for the channel path based on the channel characteristic; Based on the determined channel characteristics, the Accused MoCA Instrumentalities determine an optimum bit loading for data communication, a core function of MoCA technology. ¶129, ¶137 col. 4:59-60
transmitting a response message from the second device to the first device...the response message including the bit loading; The Accused MoCA Instrumentalities transmit response messages containing the determined bit loading information to other nodes in the network. ¶129, ¶137 col. 4:61-64
transmitting a data message from the first device to the second device over the coaxial cable network using the bit loading. The Accused MoCA Instrumentalities transmit data between nodes using the determined, optimized bit loading scheme as required by the MoCA standards. ¶129, ¶137 col. 4:65-67
  • Identified Points of Contention:
    • Scope Questions: A central question will be whether mere compliance with the MoCA standard constitutes infringement of every element of claim 1. The analysis may focus on whether the standard allows for non-infringing alternatives or if the specific implementation in the Accused MoCA Instrumentalities meets each claimed step.
    • Technical Questions: What evidence does the complaint provide that the signals transmitted between the accused devices function as the claimed "probe message" for the specific purpose of "determining a bit loading" as opposed to other network management functions?

U.S. Patent No. 7,594,249 Infringement Allegations

Claim Element (from Independent Claim 10) Alleged Infringing Functionality Complaint Citation Patent Citation
A broadband local area network... Comcast deploys the Accused MoCA Instrumentalities to form a local area network over existing coaxial cable. ¶163, ¶172 col. 3:11-15
a filter located at the point of entry of building wiring that rejects network signals...such that the rejected network signals...are reflected by the filter back into all branches of the building wiring; The complaint alleges that the Accused MoCA Instrumentalities, when deployed, create a network that necessarily meets this limitation, enabling inter-node communication. ¶160, ¶166 col. 2:13-22
a plurality of terminal devices connected to the wiring branches; The Accused MoCA Instrumentalities (e.g., gateways, client set-top boxes) are the claimed terminal devices connected to the coaxial wiring. ¶86, ¶163 col. 3:15-16
each terminal device capable of communicating with other terminal devices via the reflected signal path created by the filter; The Accused MoCA Instrumentalities are alleged to communicate with each other using the network architecture enabled by MoCA compliance. ¶160, ¶166 col. 2:13-22
wherein the terminal devices perform equalization on the received signal that restores a flat frequency response to overcome communication channel impairments caused by the reflected signals. The Accused MoCA Instrumentalities, as MoCA-compliant devices, necessarily perform equalization to function in the impaired coaxial environment. ¶160, ¶166 col. 3:19-22
  • Identified Points of Contention:
    • Scope Questions: Does the term "filter" as used in the patent require a specific, discrete component, or can it be construed to cover any system configuration or impedance mismatch at the point of entry that has the functional effect of reflecting signals back into the premises?
    • Technical Questions: What evidence does the complaint provide that the accused system, as deployed by Comcast, actually contains a component functioning as the claimed reflective "filter" at the point of entry, versus achieving inter-node communication through other mechanisms permitted by the MoCA standard?

V. Key Claim Terms for Construction

  • The Term: "probe message" (from ’518 Patent, claim 1)
  • Context and Importance: The infringement theory for the ’518 Patent is premised on the accused devices sending these messages to characterize the network. The definition of "probe message" is therefore central to determining whether the signals transmitted by the accused devices meet this limitation. Practitioners may focus on this term because its scope will determine whether general-purpose network maintenance signals fall within the claim.
  • Intrinsic Evidence for Interpretation:
    • Evidence for a Broader Interpretation: The abstract describes probe messages functionally as being "sent between devices to characterize the communication channel and determine optimum bit loading" (’518 Patent, Abstract). This functional language may support a broader construction covering various types of channel-sounding signals.
    • Evidence for a Narrower Interpretation: The detailed description discloses specific types of probes, such as an "echo profile probe" for link optimization and other probes for "hardware calibration" (’518 Patent, col. 8:38-68). This may support a narrower construction limited to signals performing these specific, disclosed functions.
  • The Term: "a filter...that rejects network signals...such that the rejected network signals...are reflected" (from ’249 Patent, claim 10)
  • Context and Importance: This element describes the core mechanism of the invention. Whether the accused system infringes the ’249 Patent will depend on whether any part of its architecture at the point of entry can be defined as this reflective "filter." Practitioners may focus on this term because it is the key structural limitation upon which infringement hinges.
  • Intrinsic Evidence for Interpretation:
    • Evidence for a Broader Interpretation: The specification suggests that a reflection can be created by an "impedance mismatch" and that the "filter" can be implemented as such (US 7,594,249 B2, col. 4:18-22). This could support construing "filter" to be any component or interface that creates a functional impedance mismatch, not just a traditional circuit filter.
    • Evidence for a Narrower Interpretation: The patent explicitly illustrates specific filter embodiments, including a signal splitter with a mismatched termination and a filter comprised of discrete circuit components like an inductor and capacitor (US 7,594,249 B2, FIG. 3). This may support a narrower construction limited to the specific structures disclosed.

VI. Other Allegations

  • Indirect Infringement: The complaint alleges that Comcast actively induces infringement by providing its customers with the Accused MoCA Instrumentalities along with "specific instructions and/or assistance (including installation and maintenance)" on how to create and use the infringing MoCA network (Compl. ¶148, ¶181). It further alleges contributory infringement on the basis that the Accused MoCA Instrumentalities have no substantial non-infringing uses and are especially made or adapted for infringing the patents (Compl. ¶151, ¶184).
  • Willful Infringement: Willfulness allegations are based on Comcast’s alleged knowledge of the patents and its infringing activities stemming from the First Case. The complaint asserts Comcast has been on notice since at least its acceptance of service of the original complaint in the First Case on February 16, 2023, and that its continued sale and deployment of the accused products demonstrates an intent to willfully infringe (Compl. ¶75, ¶141).

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

  • A central issue will be one of necessary infringement: does compliance with the MoCA industry standard, as alleged by the Plaintiff for all twelve patents, inherently require practicing the specific limitations of each asserted claim? The resolution may depend on whether the standard allows for non-infringing implementations or whether Defendant’s specific accused products can be technically distinguished from the patent claims.
  • A threshold question will be the impact of prior adjudications: given that nine of the twelve asserted patents have already received adverse rulings on patentability or eligibility from a district court or the PTAB in related proceedings, a primary focus will be on the viability of Plaintiff's pending or future appeals of those decisions, without which the corresponding claims in this case would likely be invalid.
  • For patents directed to specific network architectures, such as the ’249 Patent, a key evidentiary question will be one of structural correspondence: does the accused system, as deployed by Comcast in customers' homes, contain a physical component that functions as the claimed reflective "filter" at the point-of-entry, or is inter-node communication achieved through an alternative mechanism permissible under the MoCA standard?