DCT
2:26-cv-00053
Encryptawave Tech LLC v. Sonos Inc
Key Events
Complaint
I. Executive Summary and Procedural Information
- Parties & Counsel:
- Plaintiff: Encryptawave Technologies LLC (Illinois)
- Defendant: Sonos, Inc. (Delaware)
- Plaintiff’s Counsel: Mann Law Group; Direction IP Law
- Case Identification: 2:26-cv-00053, W.D. Wash., 01/07/2026
- Venue Allegations: Venue is alleged to be proper based on Defendant having a business location within the Western District of Washington.
- Core Dispute: Plaintiff alleges that Defendant’s Wi-Fi-enabled smart speakers and soundbars, which utilize the WPA2 security standard, infringe a patent related to methods for dynamic security authentication in wireless networks.
- Technical Context: The dispute centers on the technical protocols for establishing secure connections on wireless networks, a foundational technology for all modern Wi-Fi-enabled consumer devices.
- Key Procedural History: The complaint notes that during the patent's prosecution, the examiner allowed the relevant claims on the basis that the prior art did not teach the combination of installing a node identifier at a first node, sending that information to a second node, and synchronously regenerating an authentication key at both nodes based on that information.
Case Timeline
| Date | Event |
|---|---|
| 2003-03-13 | ’664 Patent Priority Date |
| 2007-06-19 | ’664 Patent Issue Date |
| 2026-01-07 | Complaint Filing Date |
II. Technology and Patent(s)-in-Suit Analysis
U.S. Patent No. 7,233,664 - *"Dynamic Security Authentication for Wireless Communication Networks"*
The Invention Explained
- Problem Addressed: The patent addresses vulnerabilities in then-existing wireless security protocols, which often relied on static or semi-static encryption keys. Such keys, whether in symmetric or public-key systems, were susceptible to "insider" or "super-user" attacks, where a privileged user could steal the key and compromise past and future communications ('664 Patent, col. 2:1-6, col. 2:41-48). The patent also identifies the weakness of standards like Wired Equivalent Privacy (WEP), which failed to protect wireless networks primarily because it relied on a single, static shared key (Compl. ¶10; '664 Patent, col. 4:18-24).
- The Patented Solution: The invention proposes a method for secure authentication where an "authentication key" is continuously and synchronously regenerated at two different network nodes (e.g., a device and an access point). This regeneration is based on shared "node identifier information" and is managed by daemons at each node, ensuring that the keys are constantly changing and limiting the window of opportunity for an attacker ('664 Patent, Abstract; col. 5:25-33).
- Technical Importance: This approach sought to provide robust, automated, and continuous security for mobile wireless devices without the high computational overhead associated with some public-key cryptography systems (Compl. ¶11; '664 Patent, col. 4:29-36).
Key Claims at a Glance
- The complaint asserts independent claim 1 ('664 Patent, col. 23:3-19).
- The essential elements of claim 1 are:
- Providing a node identifier comprising an address and an initial authentication key.
- Installing the node identifier at a first network node.
- Storing the node identifier at a second network node.
- Sending node identifier information from the first network node to the second network node.
- Synchronously regenerating an authentication key at two network nodes based upon the node identifier information.
III. The Accused Instrumentality
Product Identification
- The accused instrumentalities are a range of Sonos smart speakers and soundbars, including the Era 300, Move 2, Arc, Beam, and others (Compl. ¶13). The complaint uses the Era 300 as an exemplary product (Compl. ¶13).
Functionality and Market Context
- The accused products are audio devices that connect to wireless local area networks via Wi-Fi. The infringement allegations focus on their use of the Wi-Fi Protected Access 2 (WPA2) security protocol, which is based on the IEEE 802.11i standard, to establish secure connections with Wi-Fi access points (Compl. ¶14). The complaint does not provide sufficient detail for analysis of the products' commercial importance or market positioning.
IV. Analysis of Infringement Allegations
'664 Patent Infringement Allegations
| Claim Element (from Independent Claim 1) | Alleged Infringing Functionality | Complaint Citation | Patent Citation |
|---|---|---|---|
| providing a node identifier comprising an address and an initial authentication key | The accused system utilizes a MAC address (the address) and a user-provided WPA2 password, which functions as a Pre-Shared Key (PSK) or Pairwise Master Key (PMK) (the initial authentication key). | ¶15 | col. 5:37-40 |
| installing the node identifier at a first network node | The Sonos device is manufactured with a unique MAC address, and the user-configured WPA2 password/PSK is stored on the device to authenticate with access points. | ¶16 | col. 5:40-42 |
| storing the node identifier at a second network node | A Wi-Fi access point or router stores the WPA2 password/PSK and the MAC address of the connecting Sonos device for use in future authentication. | ¶17 | col. 5:42-44 |
| sending node identifier information from a first network node to a second network node | During the WPA2 4-way handshake, the Sonos device (supplicant) and the access point (authenticator) exchange messages containing their MAC addresses and information derived from the shared PMK. The complaint provides a diagram illustrating the messages exchanged between a supplicant and an authenticator (Compl. p. 15). | ¶18, p. 28 | col. 5:44-46 |
| synchronously regenerating an authentication key at two network nodes based upon node identifier information | Both the Sonos device and the access point use the MAC addresses and the PMK to derive a new Pairwise Transient Key (PTK), which serves as the temporal authentication and encryption key for the session. The complaint provides a diagram from the IEEE standard showing the derivation of the PTK from the PMK (Compl. p. 33). | ¶18, p. 34 | col. 5:46-50 |
- Identified Points of Contention:
- Scope Questions: A central question will be whether the WPA2 standard's session-based key establishment protocol constitutes "synchronously regenerating an authentication key" as contemplated by the patent. The patent specification describes an ongoing, periodic process managed by daemons ('664 Patent, col. 5:29-33), which may create a dispute over whether the one-time key derivation at the start of a WPA2 session meets this limitation.
- Technical Questions: The analysis may turn on whether the derivation of a Pairwise Transient Key (PTK) from a Pairwise Master Key (PMK) in the WPA2 protocol is technically equivalent to "regenerating" the key. A court may need to determine if this is a regeneration of the original key or the creation of a new, distinct session key from the original key, and whether that distinction matters under the patent's claims. The complaint’s theory relies entirely on mapping the public IEEE 802.11i standard onto the patent's claims, which may be contested.
V. Key Claim Terms for Construction
The Term: "synchronously regenerating an authentication key"
Context and Importance: This term is the central limitation of the asserted method claim. Its construction will determine whether the accused WPA2 key handshake process, which occurs at the initiation of a communication session, falls within the scope of the claim.
Intrinsic Evidence for Interpretation:
- Evidence for a Broader Interpretation: The plain language of the claim does not specify a required frequency or duration for the regeneration, only that it is "synchronous" and based on "node identifier information." Plaintiff may argue this language is broad enough to cover the coordinated key derivation process in the WPA2 handshake.
- Evidence for a Narrower Interpretation: The specification repeatedly describes the invention using daemons at each node that "regenerate new dynamic authentication keys (DAKs) every δt and maintain a corresponding number-regeneration-counter" ('664 Patent, col. 5:29-33). Defendant may argue this description limits the claim's scope to a continuous, time-based regeneration process, distinct from a session-initiation protocol.
The Term: "node identifier information"
Context and Importance: The infringement theory depends on mapping the messages of the WPA2 handshake to this term. The definition will be critical to establishing whether the accused products perform the "sending" step as claimed.
Intrinsic Evidence for Interpretation:
- Evidence for a Broader Interpretation: The claim uses the word "information," not the full "node identifier." Plaintiff may argue that sending MAC addresses and values derived from the initial key (as occurs in the WPA2 handshake) constitutes sending "information" based upon the node identifier, thereby satisfying the claim.
- Evidence for a Narrower Interpretation: Defendant may argue that the term requires sending information that more directly represents the complete "node identifier" (address and key) as a unit, rather than the more complex and derivative data exchanged during the WPA2 protocol.
VI. Other Allegations
The complaint does not contain allegations of indirect or willful infringement.
VII. Analyst’s Conclusion: Key Questions for the Case
- A core issue will be one of definitional scope: can the term "synchronously regenerating an authentication key," which the patent specification links to a continuous, daemon-managed process, be construed to cover the standardized, session-initiation key derivation protocol (the "4-Way Handshake") of WPA2/IEEE 802.11i?
- A key evidentiary question will be one of technical application: does the complaint demonstrate that the operation of a public industry standard (WPA2) is, in fact, an implementation of the specific, proprietary method described and claimed in the ’664 patent, or is there a fundamental mismatch between the patented invention and the accused standard protocol?