Missed Call LLC v. Twilio Inc

I. Executive Summary and Procedural Information

• Parties & Counsel:
  • Plaintiff: Missed Call, LLC (Texas)
  • Defendant: Twilio Inc. (Delaware)
  • Plaintiff’s Counsel: Ramey LLP
• Case Identification: 3:24-cv-00681, W.D. Tex., 10/24/2023
• Venue Allegations: Venue is alleged to be proper based on Defendant having a regular and established place of business in the Western District of Texas and committing alleged acts of infringement within the district.
• Core Dispute: Plaintiff alleges that Defendant’s telecommunication systems and services infringe a patent related to methods for providing a user with an indication about the cause of a missed telephone call.
• Technical Context: The technology operates in the field of telecommunications, aiming to enhance user notifications by distinguishing whether a missed call was terminated by the caller or by a network timeout.
• Key Procedural History: The complaint does not mention any prior litigation, inter partes review (IPR) proceedings, or licensing history related to the patent-in-suit.

Case Timeline

Date	Event
2010-07-21	’872 Patent Priority Date (based on PCT filing)
2016-12-27	’872 Patent Issue Date
2023-10-24	Complaint Filing Date

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

• Patent Identification: U.S. Patent No. 9,531,872, "Communication Apparatus For Providing An Indication About A Missed Call, And Method Thereof," issued December 27, 2016.

The Invention Explained

• Problem Addressed: The patent identifies a deficiency in conventional systems where a user receives a "missed call" notification but has no information about why the call was missed. The user cannot determine if the caller hung up after a short time or if the call attempt persisted until a network timeout, making it difficult to "recognize the importance of a missed call" (U.S. Patent No. 9,531,872, col. 1:47-49).
• The Patented Solution: The invention describes a communication apparatus that analyzes the technical reason for a call's disconnection. It accomplishes this by "extracting a cause value contained in a cause information element" that is sent from the telecommunications network when a call ends without being answered (’872 Patent, Abstract). This "cause value" explicitly indicates whether the disconnection was initiated by the calling user (e.g., "NORMAL CLEARING") or by the network (e.g., "RECOVERY ON TIME EXPIRY"), allowing the apparatus to provide a more meaningful notification to the user about the call's potential urgency (’872 Patent, col. 4:41-54, col. 4:55-58).
• Technical Importance: This method moves beyond simply counting rings, as disclosed in prior art, to analyze network-level signaling data, thereby providing qualitative context about the caller's intent to the recipient of a missed call (’872 Patent, col. 2:11-18).

Key Claims at a Glance

• The complaint asserts claims 1-13, with claims 1 and 10 being independent (Compl. ¶9).
• Independent Claim 1 of the ’872 Patent recites:
  • A "communication apparatus" comprising:
  • "receiving means" for receiving an incoming call;
  • a "control unit" to process the call;
  • "output means" for providing information to a user;
  • "processing means" for extracting a "cause value" from a network "cause information element" and outputting an indication related to a missed call;
  • wherein if the "cause value indicates that the received incoming call was cleared by the caller," the apparatus outputs an indication that the caller caused the missed call; and
  • wherein if the "cause value consequently indicates that the received incoming call was cleared by the network," the apparatus outputs an indication that the network caused the missed call and that the call "was urgent."
• The complaint reserves the right to assert all dependent claims (Compl. ¶9).

III. The Accused Instrumentality

Product Identification

• The complaint does not identify specific accused products by name. It broadly refers to Defendant’s "systems, products, and services that facilitate providing of an indication of a missed telephone call" (Compl. ¶9).

Functionality and Market Context

• The complaint alleges that Defendant "maintains, operates, and administers" these systems and that Defendant "put the inventions claimed by the ’872 patent into service (i.e., used them)" (Compl. ¶9). It does not, however, provide any technical details about how Defendant's systems operate or what specific features are alleged to infringe. The complaint makes general allegations about Defendant deriving "substantial revenue from goods and services provided to individuals in Texas" but offers no specific market context for the accused functionalities (Compl. ¶6).

IV. Analysis of Infringement Allegations

The complaint references an "exemplary table included as Exhibit A" to support its infringement allegations but does not include the exhibit in the filing (Compl. ¶10). In the absence of this claim chart, the infringement theory must be drawn from the complaint's narrative allegations. The complaint asserts that Defendant's systems and services perform the function of "providing of an indication of a missed telephone call" in a way that infringes claims 1-13 of the ’872 patent (Compl. ¶9). It does not, however, explain how the accused systems allegedly meet the specific limitations of the claims, such as extracting a network "cause value."

No probative visual evidence provided in complaint.

• Identified Points of Contention:
  • Technical Questions: A central evidentiary issue will be whether Plaintiff can produce evidence that Defendant’s systems actually perform the core function of the claimed invention: specifically, "extracting a cause value contained in a cause information element sent from a network" (’872 Patent, col. 6:50-55). The complaint provides no facts to support this allegation. The case will question what proof exists that Defendant's platform differentiates between a caller-initiated hang-up and a network-initiated timeout as the basis for a missed call notification.
  • Scope Questions: The claims are directed to a "communication apparatus," which the patent specification repeatedly illustrates as a user-end device like a "mobile phone" or "fixed phone" (’872 Patent, col. 3:15-18). The complaint accuses Defendant’s "systems, products, and services," which may exist primarily as a cloud-based software platform. This raises the question of whether Defendant’s network-side infrastructure can be considered a "communication apparatus" within the meaning of the claims.

V. Key Claim Terms for Construction

• The Term: "processing means for extracting a cause value..."

• Context and Importance: This term, appearing in independent claim 1, is drafted in means-plus-function format under 35 U.S.C. § 112(f). Its construction will be critical because the scope of the claim is limited to the corresponding structure described in the specification and its equivalents. The infringement analysis will depend entirely on whether Defendant’s systems use a structure that is identical or equivalent to what is disclosed in the patent for performing the recited function.

• Intrinsic Evidence for Interpretation:

  • Evidence for a Broader Interpretation: The function itself is broadly stated as "extracting a cause value contained in a cause information element sent from a network" (’872 Patent, col. 6:50-53).
  • Evidence for a Narrower Interpretation: The corresponding structure is the "processing means 40" linked to the "control unit 20" (’872 Patent, Fig. 1; col. 4:41-43). The specification links this structure to specific telecommunication standards, such as ITU-T Q.931 and 3GPP TS 24.008, and the processing of specific message types like a "CC DISCONNECT message" (’872 Patent, col. 4:1-4, col. 4:59-64). This suggests the structure is a processor executing an algorithm designed to parse these specific standardized messages to find cause values like "NORMAL CLEARING" or "RECOVERY ON TIME EXPIRY" (’872 Patent, col. 4:55-58).

• The Term: "communication apparatus"

• Context and Importance: Practitioners may focus on this term because Defendant provides cloud-based services, whereas the patent predominantly describes a physical, user-end device. The definition of "apparatus" will determine whether the claims can read on Defendant's distributed, server-side systems.

• Intrinsic Evidence for Interpretation:

  • Evidence for a Broader Interpretation: The term itself is not inherently limited, and the claims do not explicitly restrict the apparatus to a mobile handset.
  • Evidence for a Narrower Interpretation: The specification states that the apparatus "comprises a mobile phone" or "a fixed phone" (’872 Patent, col. 3:15-18). The problem solved by the invention is framed from the perspective of the "called user" and their physical device (’872 Patent, col. 1:19-34). Figure 1 depicts a single, self-contained unit with user-facing components like "output means" (30) and "input means" (31), reinforcing the interpretation of a user terminal.

VI. Other Allegations

• Indirect Infringement: The complaint alleges inducement by asserting that Defendant "actively encouraged or instructed others (e.g., its customers...)" to use its services in an infringing manner (Compl. ¶11). It alleges contributory infringement by claiming there are "no substantial noninfringing uses" for Defendant's services (Compl. ¶12).
• Willful Infringement: The complaint alleges that Defendant has known of the ’872 patent and its infringement "from at least the filing date of the lawsuit," establishing a basis for post-filing willfulness (Compl. ¶¶ 11-12). It also reserves the right to amend if pre-suit knowledge is discovered (Compl. ¶11, n.1).

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

1. A central issue will be one of definitional scope: can the term "communication apparatus", which the patent specification describes as a user-side device like a mobile phone, be construed to cover Defendant’s distributed, cloud-based telecommunication services?

2. A key evidentiary question will be one of technical proof: what evidence can Plaintiff offer to demonstrate that Defendant’s systems perform the specific, recited function of "extracting a cause value" from standardized network disconnection messages to determine if a missed call was terminated by the caller or the network?

3. The case will likely turn on the application of means-plus-function claiming: because the core technical limitations are drafted in this format, the dispute will focus on whether the specific algorithms and structures disclosed in the ’872 patent are present, either identically or equivalently, in Defendant’s accused systems.