DCT

1:24-cv-00116

Bandspeed LLC v. VeSync Co Ltd

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I. Executive Summary and Procedural Information

  • Parties & Counsel:
  • Case Identification: Bandspeed, LLC v. Vesync Co., Ltd., 1:24-cv-00116, W.D. Tex., 01/31/2024
  • Venue Allegations: Venue is alleged to be proper as Defendant is a foreign corporation subject to personal jurisdiction in the district.
  • Core Dispute: Plaintiff alleges that Defendant’s Bluetooth-enabled consumer electronic products infringe a portfolio of twelve patents related to adaptive frequency hopping for managing wireless communications channels.
  • Technical Context: The technology at issue, adaptive frequency hopping, is a method for wireless devices to dynamically avoid crowded or noisy communication channels, which is particularly significant for technologies like Bluetooth that operate in the heavily used 2.4 GHz ISM band.
  • Key Procedural History: The complaint alleges that Plaintiff sent notice letters to Etekcity Corporation, and by extension to Defendant, on May 21, 2019, May 11, 2020, and April 6, 2021, identifying the patents-in-suit and the nature of the alleged infringement. These letters may form the basis for allegations of pre-suit knowledge and willful infringement.

Case Timeline

Date Event
2001-01-25 Earliest Priority Date for all Patents-in-Suit
2006-04-11 U.S. Patent No. 7,027,418 Issues
2009-01-13 U.S. Patent No. 7,477,624 Issues
2009-08-04 U.S. Patent No. 7,570,614 Issues
2011-03-08 U.S. Patent No. 7,903,608 Issues
2013-09-24 U.S. Patent No. 8,542,643 Issues
2014-10-28 U.S. Patent No. 8,873,500 Issues
2016-06-28 U.S. Patent No. 9,379,769 Issues
2018-01-30 U.S. Patent No. 9,883,520 Issues
2019-05-21 Plaintiff sends first notice letter to Defendant
2020-03-24 U.S. Patent No. 10,602,528 Issues
2020-05-11 Plaintiff sends follow-up notice letter to Defendant
2020-09-29 U.S. Patent No. 10,791,565 Issues
2021-01-05 U.S. Patent No. 10,887,893 Issues
2021-04-06 Plaintiff sends supplemental notice letter to Defendant
2024-01-31 Complaint Filed

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

U.S. Patent No. 7,027,418 - “Approach for Selecting Communications Channels Based on Performance”

The Invention Explained

  • Problem Addressed: The patent describes the "coexistence problem" that arises when frequency hopping (FH) communication systems, like Bluetooth, operate in the same frequency band as non-frequency hopping (NFH) systems, like Wi-Fi (U.S. Patent No. 7,027,418, col. 1:11-15, col. 3:44-54). This shared spectrum use leads to interference, resulting in data transmission errors, increased power consumption, and degraded performance for both systems (U.S. Patent No. 7,027,418, col. 3:55-4:14).
  • The Patented Solution: The invention provides a method for an FH system to adaptively avoid interference by dynamically selecting which communication channels to use. The system determines the performance of available channels, selects a set of "good" channels based on specified criteria, and communicates using that set. It then periodically re-evaluates channel performance to select a new set of channels, allowing it to adapt to changing interference conditions over time (U.S. Patent No. 7,027,418, Abstract; Fig. 1A).
  • Technical Importance: This adaptive approach allows FH systems to maintain reliable communication links in increasingly crowded unlicensed radio bands by intelligently avoiding channels occupied by other systems or sources of noise (U.S. Patent No. 7,027,418, col. 4:15-24).

Key Claims at a Glance

  • The complaint asserts independent method claim 5 (Compl. ¶120).
  • Essential elements of claim 5 include:
    • Selecting a first set of two or more communication channels at a first time based on channel performance and a specific "voting" criteria, where a channel must receive a specified number of affirmative votes and no negative votes to be selected.
    • Selecting a second set of channels at a later time based on performance and the same criteria.
    • Operating as a frequency hopping system where only one channel is used at each hop.
    • Generating and transmitting data that identifies the first and second sets of channels to other participants in the system.

U.S. Patent No. 7,477,624 - “Approach for Managing the Use of Communications Channels Based on Performance”

The Invention Explained

  • Problem Addressed: As with the related '’418 Patent, this patent addresses the technical challenge of interference in shared frequency bands, which degrades the performance of wireless communication systems (’624 Patent, col. 1:11-15, col. 3:44-54).
  • The Patented Solution: The patent describes a communication device (rather than a method) that implements an adaptive frequency hopping solution. The device comprises a processor and memory with instructions to select a first set of channels based on performance, use them for a period, and then select and switch to a second set of channels at a later time. A key aspect of the solution is causing the selected channel sets to be loaded into registers on both the transmitting and receiving devices to coordinate the frequency hopping (’624 Patent, Abstract; col. 5:20-32).
  • Technical Importance: By embodying the adaptive channel selection logic within a device, the patent provides a concrete apparatus for implementing robust frequency hopping in real-world products operating in congested spectrums (’624 Patent, col. 4:15-24).

Key Claims at a Glance

  • The complaint asserts claim 15, which depends from independent device claim 13 (Compl. ¶137).
  • Essential elements of independent claim 13 include:
    • A communications device with a memory and a processor.
    • Instructions that cause the processor to select a first set of channels based on performance at a first time, and a second set of channels at a second time.
    • A transceiver that uses the first set of channels for a first period of time and then uses the second set of channels for a second period of time.
    • Instructions that, after selecting each set, cause that set of channels to be loaded into a register of the communications device and a register of another communications device.

U.S. Patent No. 7,570,614 - “Approach for Managing Communications Channels Based on Performance”

  • Technology Synopsis: This patent claims a method performed by a master device in a master-slave network. The master selects a "bad" channel, informs a slave not to use it, and then receives performance quality data from the slave for other channels to update its channel data (’614 Patent, Abstract). This allows the master to maintain a dynamic map of channel quality based on feedback from slave devices.
  • Asserted Claims: The complaint asserts independent method claim 100 (Compl. ¶154).
  • Accused Features: The complaint accuses "Infringing Bluetooth Classic Products" of infringement, alleging they operate in a master-slave piconet and perform adaptive frequency hopping compliant with the Bluetooth Core Specification (Compl. ¶28, 46, 153).

U.S. Patent No. 7,903,608 - “Approach for Managing the Use of Communications Channels Based on Performance”

  • Technology Synopsis: This patent claims a communication device that adaptively selects different sets of communication channels over time, with the specific limitation that the number of distinct channels in the first set varies from the number of distinct channels in the second set (’608 Patent, Abstract; col. 3:56-62). This allows the device to change not just which channels are used, but also how many channels are in the hopping set.
  • Asserted Claims: The complaint asserts independent device claim 1 (Compl. ¶171).
  • Accused Features: The complaint accuses both "Infringing Bluetooth Classic Products" and "Infringing Bluetooth LE Products," which allegedly comply with Bluetooth specifications providing for adaptive frequency hopping (Compl. ¶28, 70, 170).

U.S. Patent No. 8,542,643 - “Approach for Managing the Use of Communications Channels Based on Performance”

  • Technology Synopsis: This patent discloses a method of managing frequency hopping channels by maintaining a "default channel register" and a "good channel register." When the system needs to hop to a channel that is designated as "bad" in the default register, it replaces it on-the-fly with a channel selected from the "good channel register" (’643 Patent, Abstract). This provides a mechanism for substituting known-good channels for known-bad ones within a hopping sequence.
  • Asserted Claims: The complaint asserts claim 5, which depends from independent method claim 1 (Compl. ¶190).
  • Accused Features: The complaint accuses both "Infringing Bluetooth Classic Products" and "Infringing Bluetooth LE Products" of practicing adaptive frequency hopping (Compl. ¶189).

U.S. Patent No. 8,873,500 - “Approach for Managing the Use of Communications Channels Based on Performance”

  • Technology Synopsis: This patent describes a frequency hopping device that starts communicating on a default hopping sequence, tests the channels to select a better subset, communicates on that "adapted" subset, monitors the subset's performance, and then reverts to the default sequence based on monitoring results or after a specified time (’500 Patent, Abstract). This creates a cycle of adapting to current conditions and periodically reverting to re-evaluate the full channel map.
  • Asserted Claims: The complaint asserts claim 28, which depends from independent device claim 16 (Compl. ¶209).
  • Accused Features: The complaint accuses both "Infringing Bluetooth Classic Products" and "Infringing Bluetooth LE Products" of practicing adaptive frequency hopping (Compl. ¶208).

U.S. Patent No. 9,379,769 - “Approach for Managing the Use of Communications Channels Based on Performance”

  • Technology Synopsis: This patent claims a wireless device that monitors a plurality of communication channels, classifies them as "good" or "bad" based on the results, transmits this classification information to another device, and then communicates using the "good" channels while avoiding the "bad" ones (’769 Patent, Abstract).
  • Asserted Claims: The complaint asserts independent device claim 1 (Compl. ¶228).
  • Accused Features: The complaint accuses both "Infringing Bluetooth Classic Products" and "Infringing Bluetooth LE Products" of practicing adaptive frequency hopping (Compl. ¶227).

U.S. Patent No. 9,883,520 - “Approach for Managing the Use of Communications Channels Based on Performance”

  • Technology Synopsis: This patent discloses a device that sends packet data specifying a subset of channels to be used for frequency hopping, along with timing information on when to begin using that subset (’520 Patent, Abstract). The device then uses a channel from the full set if it is on the old hopping sequence but switches to a channel from the new subset at the specified time.
  • Asserted Claims: The complaint asserts independent device claim 1 (Compl. ¶247).
  • Accused Features: The complaint accuses both "Infringing Bluetooth Classic Products" and "Infringing Bluetooth LE Products" of practicing adaptive frequency hopping (Compl. ¶246).

U.S. Patent No. 10,602,528 - “Approach for Managing the Use of Communications Channels Based on Performance”

  • Technology Synopsis: This patent describes a device that manages power levels by determining a subset of channels and excluding those with performance outside a target threshold (’528 Patent, Abstract). It sends packet data defining this current subset and then uses a channel from that subset, before causing a next instance of the subset to be determined and sent.
  • Asserted Claims: The complaint asserts independent device claim 1 (Compl. ¶266).
  • Accused Features: The complaint accuses both "Infringing Bluetooth Classic Products" and "Infringing Bluetooth LE Products" of practicing adaptive frequency hopping (Compl. ¶265).

U.S. Patent No. 10,791,565 - “Approach for Managing the Use of Communications Channels Based on Performance”

  • Technology Synopsis: This patent is similar to the '528 patent, claiming a device that manages power level by determining a subset of channels and excluding those with performance outside a target threshold (’565 Patent, Abstract). It then sends packet data defining this subset and uses a channel from it for frequency hopping.
  • Asserted Claims: The complaint asserts independent device claim 1 (Compl. ¶285).
  • Accused Features: The complaint accuses both "Infringing Bluetooth Classic Products" and "Infringing Bluetooth LE Products" of practicing adaptive frequency hopping (Compl. ¶284).

U.S. Patent No. 10,887,893 - “Approach for Managing the Use of Communications Channels Based on Performance”

  • Technology Synopsis: This patent claims a device adapted to manage power consumption by assessing channel performance to determine if using a different channel would enable improved performance (’893 Patent, Abstract). If the assessment indicates improvement is possible, the device causes communication to be performed on that different, better-performing channel.
  • Asserted Claims: The complaint asserts independent device claim 1 (Compl. ¶304).
  • Accused Features: The complaint accuses "Infringing Bluetooth Classic Products" of practicing adaptive frequency hopping (Compl. ¶303).

III. The Accused Instrumentality

Product Identification

The complaint identifies two categories of accused products:

  1. "Infringing Bluetooth Classic Products": Devices that comply with Bluetooth Core Specification Version 2.0+EDR or higher (Compl. ¶28). An exemplary product is the Etekcity White Noise Machine with Bluetooth Speaker (Model No. EWN-S12) (Compl. ¶39).
  2. "Infringing Bluetooth LE Products": Devices that comply with the Bluetooth low energy protocol in Version 4.0 or later of the Bluetooth Core Specification (Compl. ¶70). An exemplary product is the Etekcity ESF24 Smart Fitness Scale (Compl. ¶72).

Functionality and Market Context

The core accused functionality is the implementation of "adaptive frequency hopping" (AFH), which the complaint alleges is material to the patented inventions and required for compliance with the relevant Bluetooth standards (Compl. ¶33, 36, 41, 76). The complaint includes a photograph from an FCC filing of the internal circuit board of the Etekcity White Noise Machine, identifying the Bluetooth chipset and printed circuit board antenna (Compl. p. 7, Photo 4). Defendant allegedly markets these products, under brands including Etekcity, Cosori, and Levoit, as small home appliances for the U.S. online market through its own website and third-party retailers (Compl. ¶97-98, 106-107). A screenshot from Defendant's website shows the Etekcity ESF24 Smart Fitness Scale for sale, noting its connectivity with the VeSync app (Compl. p. 13).

IV. Analysis of Infringement Allegations

The complaint does not provide claim charts. The following tables summarize the infringement theory based on the narrative allegations against the exemplary products and the asserted independent claims.

U.S. Patent No. 7,027,418 Infringement Allegations

Claim Element (from Independent Claim 5) Alleged Infringing Functionality Complaint Citation Patent Citation
selecting, based upon performance of a plurality of communications channels at a first time and channel selection criteria, a first set of two or more communications channels... The accused products implement "Adaptive Frequency Hopping" and are certified as compliant with Bluetooth specifications that require this functionality. ¶36, 41, 42 col. 7:5-10
wherein the channel selection criteria specifies that for a particular communications channel to be selected, the particular communications channel (a) receives a specified number of affirmative votes...and (b) does not receive a negative vote... The complaint does not specify how the accused products meet the "voting" criteria, but alleges they meet every limitation of the claim. ¶121 col. 4:51-55
selecting, based upon performance of the plurality of communications channels at a second time that is later than the first time and the channel selection criteria, a second set of two or more communications channels... The accused products are capable of changing the set of channels on which they communicate during the connection lifetime of a piconet. ¶58, 59 col. 7:40-45
wherein the communications system is a frequency hopping communications system and the plurality of communications channels correspond to a set of frequencies to be used based on a hopping sequence... The accused products are capable of operating in the 2.4 GHz ISM frequency band and participating in Bluetooth piconets using a sequence of fewer than the total available frequencies. ¶44, 46, 54 col. 3:12-14
generating first channel identification data... [and] transmitting the first channel identification data... The accused products are capable of transmitting and receiving data packets to and from other devices on multiple frequencies. ¶48-53 col. 4:56-60

U.S. Patent No. 7,477,624 Infringement Allegations

Claim Element (from Independent Claim 13) Alleged Infringing Functionality Complaint Citation Patent Citation
a memory for storing instructions; a processor that is communicatively coupled to the memory... The accused products contain a Bluetooth chipset made by Actions Technology Co., Ltd., which includes processing and memory capabilities. ¶40 col. 5:20-24
...selecting, based upon performance... a first set of two or more communications channels... [and] selecting... a second set of two or more communications channels... The accused products are capable of performing adaptive frequency hopping and changing the set of channels used for communication during a connection. ¶42, 58, 59 col. 5:25-32
a transceiver... configured to transmit to and receive from another communications device... The accused products contain a Bluetooth chipset and a PCB antenna for transmitting and receiving data packets. ¶40, 48-51 col. 2:6-14
for a first period of time, the first set of two or more communications channels is used... and for a second period of time... the second set of two or more communications channels is used... The accused products are capable of changing the set of channels used for communication during the lifetime of a piconet connection. ¶58, 59 col. 2:15-23
...after selecting the first set... causing the first set... to be loaded into a first register... and a second register of the other communications device... The complaint does not specify how the accused products load channel sets into registers, but alleges they meet every limitation of the claim. ¶138 col. 2:27-35

Identified Points of Contention

  • Technical Questions: The complaint's infringement theory rests heavily on the allegation that the accused products comply with Bluetooth standards that include AFH (Compl. ¶36, 41). A central technical question will be whether the specific AFH implementation in the accused products performs all the detailed steps required by the asserted claims. For example, what evidence demonstrates that the accused products use the specific "affirmative vote" and "no negative vote" criteria required by claim 5 of the ’418 Patent?
  • Scope Questions: The infringement analysis may focus on the scope of specific claim terms. For claim 13 of the ’624 Patent, a question arises as to whether the accused product's standard operation involves "causing the... set of... channels to be loaded into a first register... and a second register of the other communications device." The dispute may turn on whether the accused functionality can be characterized as meeting this specific register-loading limitation.

V. Key Claim Terms for Construction

  • The Term: "channel selection criteria specifies that for a particular communications channel to be selected, the particular communications channel (a) receives a specified number of affirmative votes to use the particular communications channel from a plurality of participants and (b) does not receive a negative vote from a particular participant to not use the particular communications channel" (from claim 5 of the '418 Patent).

  • Context and Importance: This term defines a specific consensus-based or "voting" mechanism for channel selection. Practitioners may focus on this term because infringement will depend on whether the accused AFH system, which is based on the Bluetooth standard, can be shown to operate according to this particular voting rule. Defendant may argue that its system uses a different, non-infringing method for classifying and selecting channels.

  • Intrinsic Evidence for Interpretation:

    • Evidence for a Broader Interpretation: The specification suggests that various approaches to channel selection may be used, stating that "other criteria may be used... that particular channels are, or are not, to be selected regardless of the test results" (’418 Patent, col. 7:38-42). This could suggest the specific voting language is merely one example of a broader "selection criteria."
    • Evidence for a Narrower Interpretation: The claim language itself is highly specific, requiring both a threshold of "affirmative votes" and the absence of any "negative vote." The patent also describes this voting method in a detailed example involving a "referendum" among a master and seven slaves, where a "passing mark" of seven out of eight votes is required (’418 Patent, Table 2, col. 17:21-48). This detailed embodiment may support a narrower construction limited to such explicit voting schemes.

  • The Term: "causing the first set of two or more communications channels to be loaded into a first register of the communications device and a second register of the other communications device" (from claim 13 of the '624 Patent).

  • Context and Importance: This term recites a specific mechanism for synchronizing the selected channel map between two devices by loading it into their respective registers. The infringement case against the accused devices will hinge on whether their operation includes this particular technical step.

  • Intrinsic Evidence for Interpretation:

    • Evidence for a Broader Interpretation: The patent states that the invention is not limited to any particular implementation and that embodiments may be in software, hardware, or a combination thereof (’624 Patent, col. 10:14-20). This may support an argument that any method of synchronizing the channel list, whether in a dedicated hardware "register" or a software memory location, falls within the claim's scope.
    • Evidence for a Narrower Interpretation: The specification includes Figure 5A, which explicitly depicts a "Register with Default Channels 520" and a "Register with Good Channels 550," illustrating a process of "loading" a table of good channels into a distinct register (’624 Patent, Fig. 5A, col. 8:36-41). This specific embodiment depicting distinct hardware-style registers could be used to argue for a narrower interpretation that excludes more generalized software-based synchronization methods.

VI. Other Allegations

  • Indirect Infringement: The complaint alleges both induced and contributory infringement for all asserted patents. The inducement allegations are based on Defendant providing products with infringing functionality and instructing customers on how to use that functionality through user manuals, SDKs, and driver software (Compl. ¶63-64, 124, 141). For example, a screenshot of a user manual for an accused product provides instructions on how to download and set up the "VeSync app" to enable the device's smart features (Compl. p. 18). Contributory infringement is alleged on the basis that the AFH functionality is a material part of the invention and that the accused products have no substantial non-infringing uses (Compl. ¶67, 131, 148).
  • Willful Infringement: Willfulness is alleged based on Defendant's knowledge of the patents from pre-suit notice letters sent by Plaintiff starting on May 21, 2019, and from the filing of the complaint itself (Compl. ¶23-27, 320). The complaint alleges that despite this knowledge, Defendant continued its infringing conduct (Compl. ¶321).

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

  • A core issue will be one of technical implementation: does the accused products' alleged compliance with the Bluetooth standard's provisions for Adaptive Frequency Hopping (AFH) necessarily meet every specific limitation of the asserted claims? The case will likely require a detailed analysis of how the accused chipsets actually select and switch channels, rather than relying on high-level allegations of standard compliance.
  • A key legal question will be one of definitional scope: can the specific "voting" mechanism of the ’418 patent and the dual-device "register loading" process of the ’624 patent be construed broadly enough to read on the functionality of standard-compliant Bluetooth devices? The outcome may depend heavily on how the court interprets these potentially narrowing claim limitations in light of the patent specifications.
  • A central evidentiary question will be one of proof: what evidence will Plaintiff present to demonstrate that the accused products perform the specific, multi-part logical functions required by the claims, beyond general assertions that the products are "capable" of such performance? The level of detail in the complaint is high, which may present challenges in proving that the accused products operate in the precise manner claimed.