Coretek Licensing LLC v. Teamviewer US Inc

I. Executive Summary and Procedural Information

• Parties & Counsel:
  • Plaintiff: Coretek Licensing LLC (Texas)
  • Defendant: Teamviewer US, Inc. (Delaware)
  • Plaintiff’s Counsel: Chong Law Firm PA; Sand, Sebolt & Wernow Co., LPA
• Case Identification: 1:20-cv-00875, D. Del., 06/28/2020
• Venue Allegations: Plaintiff alleges venue is proper in the District of Delaware because Defendant is incorporated in Delaware and thus resides in the district for patent venue purposes under TC Heartland.
• Core Dispute: Plaintiff alleges that Defendant’s Blizz communications software infringes four patents related to methods for enabling wireless devices to make network connections without using a traditional cellular network operator's Home Location Register (HLR) and for dynamically determining a device's VoIP location.
• Technical Context: The patents address technologies for routing voice and data communications over internet protocol (IP) networks, bypassing the control and tariff structures of conventional mobile network operators, a foundational concept for modern over-the-top (OTT) communication services.
• Key Procedural History: No prior litigation, licensing history, or other significant procedural events are mentioned in the complaint.

Case Timeline

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

U.S. Patent No. 8,861,512 - "METHOD OF ENABLING A WIRELESS DEVICE TO MAKE A NETWORK CONNECTION WITHOUT USING A NETWORK OPERATOR'S HOME LOCATION REGISTER," issued October 14, 2014

The Invention Explained

• Problem Addressed: The patent describes a technical landscape where wireless device users are restricted by their subscribed mobile network operator, which controls access, services, and tariffs through a central database called a Home Location Register (HLR). This control limits user choice and can result in higher costs, as operators have little incentive to allow users to select cheaper, alternative networks for calls or data. (’512 Patent, col. 1:43-65).
• The Patented Solution: The invention proposes a system that bypasses the HLR. A software module on a wireless device sends a call request, not through the standard HLR pathway, but directly to a separate server using protocols like SMS or HTTP. This server, which maintains its own location database, then decides on the most appropriate routing for the call over any available network (e.g., VoIP, other cellular networks), effectively decoupling the call routing from the user's primary mobile operator. (’512 Patent, col. 2:51-61; col. 4:22-36).
• Technical Importance: This approach provided a technical framework for enabling over-the-top (OTT) services that could operate independently of the pricing and routing constraints imposed by traditional mobile network operators. (’512 Patent, col. 2:41-50).

Key Claims at a Glance

• The complaint asserts independent claims 1, 23, and 24. (Compl. ¶21).
• Independent Claim 1 (Method):
  • A wireless device uses a downloadable software module to contact a server over a wireless link.
  • The wireless device uses the module to send data defining a call request to the server.
  • In response, a software application on the server decides the appropriate routing to a third-party end-user over available networks, all "without using the network operator's home or visitor location register."
• The complaint also asserts dependent claim 12 and reserves the right to assert additional claims. (Compl. ¶21, ¶144).

U.S. Patent No. 9,173,154 - "METHOD OF ENABLING A WIRELESS DEVICE TO MAKE A NETWORK CONNECTION WITHOUT USING A NETWORK OPERATOR'S HOME LOCATION REGISTER," issued October 27, 2015

The Invention Explained

• Problem Addressed: The '154 Patent addresses the same problem as the '512 Patent: the restrictions and costs imposed on users by the HLR-centric architecture of mobile network operators. (’154 Patent, col. 1:44-col. 2:3).
• The Patented Solution: The solution is functionally identical to that of the '512 Patent, involving a software module on a device that communicates with a server to arrange call routing over alternative networks, thereby bypassing the HLR. A key distinction is that the claims are specifically directed to a "wireless handheld cellular phone device," a more specific term than the "wireless device" recited in the '512 Patent. (’154 Patent, Abstract; col. 2:55-63).
• Technical Importance: This patent narrows the claimed invention to the specific context of cellular handsets, a primary market for over-the-top communication applications. (’154 Patent, col. 5:45-53).

Key Claims at a Glance

• The complaint asserts independent claims 1, 22, 23, and 24. (Compl. ¶35).
• Independent Claim 1 (Method):
  • A "wireless handheld cellular phone device" uses a downloadable software module to contact a server.
  • The device sends data defining a call request to the server.
  • A server application decides on routing to an end-user "without using the network operator's home or visitor location register."
• The complaint also asserts dependent claim 11 and reserves the right to assert additional claims. (Compl. ¶35, ¶144).

U.S. Patent No. 9,369,575 - "DYNAMIC VOIP LOCATION SYSTEM," issued June 14, 2016

• Technology Synopsis: The patent addresses the technical challenge of reliably determining the current IP address or "VoIP location" of a device connected to the internet, particularly a power-constrained wireless device. The invention describes an automated system where a device's software module periodically authenticates with a server and reports its current VoIP address (return path) to a database, allowing other applications to reliably establish a connection without requiring the device to constantly poll for incoming data, thus saving power. (’575 Patent, col. 2:30-44, col. 2:50-61).
• Asserted Claims: Independent claim 1. (Compl. ¶42).
• Accused Features: The complaint alleges the Blizz system infringes by detecting, determining, and storing the IP address of user devices in databases and using that information to establish VoIP calls between users. (Compl. ¶¶101-102, 104).

U.S. Patent No. 9,591,551 - "METHOD OF ENABLING A WIRELESS DEVICE TO MAKE A NETWORK CONNECTION WITHOUT USING A NETWORK OPERATOR'S HOME LOCATION REGISTER," issued March 7, 2017

• Technology Synopsis: This patent is in the same family as the '512 and '154 patents and addresses the same technical problem of bypassing the mobile operator's HLR. The solution is likewise a client-server system for arranging call routing over alternative networks. The '551 Patent's claims are directed to a "computer program product embodied on a non-transitory storage medium." (’551 Patent, Abstract; col. 2:51-61).
• Asserted Claims: Independent claims 1, 22, 23, and 24. (Compl. ¶62).
• Accused Features: The complaint accuses the Blizz software product itself, as a computer program embodied on a storage medium (e.g., a smartphone's memory), of infringement. (Compl. ¶¶109, 111).

III. The Accused Instrumentality

Product Identification

• Defendant’s "Blizz" communications software, also referred to as "TeamViewer's Blizz" smartphone application. (Compl. ¶63, ¶99).

Functionality and Market Context

• The complaint describes Blizz as a communications software solution that enables users to make calls using an Internet or IP network rather than traditional cellular voice networks. (Compl. ¶65, ¶81). The system allegedly comprises a client application (the "Blizz application" or "module") that runs on a user's device (e.g., a smartphone) and communicates with a "Blizz Server." (Compl. ¶66, ¶82). To initiate a call, the Blizz application sends an "Invite signal" to the Blizz Server, which then uses a SIP proxy to decide on the appropriate routing to connect the call to another Blizz user. (Compl. ¶67-68, ¶84). The complaint also alleges the Blizz system determines and collects device IP addresses to facilitate these connections. (Compl. ¶101).
• No probative visual evidence provided in complaint.

IV. Analysis of Infringement Allegations

’512 Patent Infringement Allegations

’154 Patent Infringement Allegations

Identified Points of Contention

• Scope Questions: The core of the dispute may turn on the scope of the negative limitation "without using a network operator's home location register." A question for the court is whether an over-the-top application like Blizz that uses a general-purpose IP network (Wi-Fi/cellular data) inherently operates "without using" the HLR in the manner claimed, or if the patent requires a more specific interaction with or circumvention of the cellular network's native call-routing architecture.
• Technical Questions: What evidence does the complaint provide that the accused Blizz server's "SIP proxy" performs the claimed function of "deciding on the appropriate routing... over all available networks"? The allegations appear to describe routing between Blizz users on the IP network, which raises the question of whether this meets the broader claim language.

V. Key Claim Terms for Construction

For the '512 Patent

• The Term: "without using a network operator's home location register"
• Context and Importance: This negative limitation is central to the invention's alleged point of novelty. The construction of this term will determine whether simply using a parallel IP network for communication (as OTT apps do) is sufficient to infringe, or if a more direct avoidance of the HLR's specific functions is required.
• Intrinsic Evidence for Interpretation:
  • Evidence for a Broader Interpretation: The specification broadly contrasts the invention with systems controlled by an HLR, stating the invention allows a user to "choose the optimal call routing without needing to use a network operator's HLR." (’512 Patent, col. 8:20-22). This could support an interpretation where any non-HLR-based routing method infringes.
  • Evidence for a Narrower Interpretation: The background extensively details the specific role of the HLR in traditional mobile roaming and call termination (e.g., using SS7 messages). (’512 Patent, col. 2:3-40). This context might support a narrower construction, suggesting the invention is aimed at systems that specifically replicate and replace these HLR functions, rather than merely using a separate, pre-existing data network like the internet.

For the '154 Patent

• The Term: "wireless handheld cellular phone device"
• Context and Importance: This term narrows the scope of the '154 Patent compared to the broader "wireless device" in the '512 Patent. Practitioners may focus on this term because it requires Plaintiff to prove the accused method was specifically performed on a device meeting this three-part definition, potentially excluding infringement scenarios on tablets, laptops, or other non-phone devices.
• Intrinsic Evidence for Interpretation:
  • Evidence for a Broader Interpretation: The specification uses terms like "wireless device" and "handheld device" interchangeably in the general description, which might suggest the "cellular phone" aspect is not a strict limitation on the underlying technology. (’154 Patent, col. 5:45-53).
  • Evidence for a Narrower Interpretation: The term itself is explicit. The choice to claim "cellular phone device" specifically, when the parent patent claimed the broader "wireless device," could be interpreted as a deliberate narrowing of scope to cover a specific embodiment, distinguishing it from other wireless-capable devices.

VI. Other Allegations

• Indirect Infringement: The complaint alleges that Defendant induced infringement "by encouraging infringement" and knowing that such acts constituted infringement. (Compl. ¶139). This suggests a theory based on Defendant encouraging end-users to install and use the Blizz software in a manner that directly infringes the asserted method and system claims.
• Willful Infringement: The complaint alleges that Defendant had knowledge of the patents-in-suit "at least as of the service of the present Complaint" and prays for enhanced damages. (Compl. ¶137; Prayer for Relief ¶f). This frames the willfulness allegation as being based on post-suit conduct.

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

• A core issue will be one of definitional scope: can the negative limitation "without using a network operator's home location register," which is central to three of the four patents, be construed to read on an over-the-top application that uses the internet for communication, or is there a technical mismatch between simply using a parallel data network and the patent's described circumvention of specific HLR functions?
• A second key question will be one of evidentiary proof and claim differentiation: how will Plaintiff distinguish infringement of the '512 Patent (claiming a "wireless device") from the '154 Patent (claiming a "wireless handheld cellular phone device"), and can it prove the accused Blizz system performs the specific dynamic location and power-saving functions required by the '575 Patent, beyond general IP address tracking?
• A final question will be technical operation: does the accused Blizz system's function of routing calls between its own users via a SIP proxy meet the claim requirement of "deciding on the appropriate routing... over all available networks," or is the claimed functionality broader than the alleged operation?