Wireless Monitoring Systems LLC v. Ametek Inc

I. Executive Summary and Procedural Information

• Parties & Counsel:
  • Plaintiff: Wireless Monitoring Systems LLC (Texas)
  • Defendant: Ametek, Inc. (Delaware)
  • Plaintiff’s Counsel: Stamoulis & Weinblatt LLC
• Case Identification: 1:18-cv-00601, D. Del., 04/20/2018
• Venue Allegations: Plaintiff alleges venue is proper in the District of Delaware because Defendant is a Delaware corporation and is therefore deemed to reside in the district.
• Core Dispute: Plaintiff alleges that Defendant’s WirelessHART-compliant industrial monitoring devices infringe a patent related to configurable circuit monitoring.
• Technical Context: The technology involves systems for monitoring the status of electrical circuits, such as those used in industrial control or security systems, to detect conditions like alarms or faults.
• Key Procedural History: The asserted patent is subject to a terminal disclaimer and is a continuation of a series of applications tracing priority back to a foreign application filed in 2000, suggesting a long prosecution history.

Case Timeline

Date	Event
2000-12-04	’893 Patent Priority Date
2014-12-16	’893 Patent Issued
2018-04-20	Complaint Filed

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

U.S. Patent No. 8,912,893 - "Circuit Monitoring Device" (issued Dec. 16, 2014)

The Invention Explained

• Problem Addressed: The patent’s background section describes the problem of "vendor lock-in" with proprietary security and building management systems. These systems often require field devices (e.g., door sensors, smoke detectors) with specific, non-interchangeable electrical resistor values, making it expensive and difficult for a system owner to switch vendors or upgrade components without completely rewiring the system or replacing all devices. (’893 Patent, col. 2:41-59).
• The Patented Solution: The invention proposes a circuit monitoring device that decouples the central monitoring unit from the specific field hardware. It achieves this by measuring a parameter of a circuit and comparing it to a set of user-adjustable threshold values stored in memory. (’893 Patent, col. 7:13-22). By allowing these thresholds to be configured, the device can be adapted to work with a wide variety of existing field devices and their different resistor values, eliminating the need for costly replacement and enabling the use of standardized hardware like programmable logic controllers (PLCs). (’893 Patent, col. 3:37-44).
• Technical Importance: This approach provides a flexible, universal solution for retrofitting or upgrading legacy security and industrial control systems, reducing dependence on the original equipment manufacturer. (’893 Patent, col. 3:25-33).

Key Claims at a Glance

• The complaint asserts "at least Claim 30" of the ’893 Patent. (Compl. ¶12).
• The essential elements of independent method Claim 30 are:
  • Receiving a parameter of a circuit using one or more configured processors.
  • Comparing a digital value corresponding to the parameter’s magnitude to a plurality of threshold values that define ranges corresponding to circuit conditions (e.g., normal, alarm).
  • Assigning a status to the digital value based on the range it falls within.
  • Transmitting the status to a central monitoring system.
• The complaint reserves the right to assert additional claims. (Compl. ¶12).

III. The Accused Instrumentality

Product Identification

• The complaint names the "Universal IV CM Model, Water Cut Monitor, and any other WirelessHART-compliant devices" sold by Defendant's Ametek Drexelbrook business unit as the accused instrumentalities ("Product"). (Compl. ¶13).

Functionality and Market Context

• The complaint alleges the accused products are part of wireless systems used for industrial applications, including monitoring sensors and actuators for condition monitoring and flexible manufacturing. (Compl. ¶15).
• Functionally, the products are alleged to operate according to the WirelessHART standard, which allows them to monitor process variables (e.g., pressure, temperature) and send "status alerts" when measurements exceed pre-configured digital values. (Compl. ¶16).
• These alerts can be configured as "HI HI Alarm," "HI Alarm," "LO Alarm," etc., which the complaint alleges constitutes assigning a status based on the measured value falling within a specific range. (Compl. p. 5).
• The products then allegedly transmit this status information wirelessly to a central system for display and management. (Compl. ¶18). The complaint provides a network diagram illustrating how field devices, access points, and a gateway communicate status to a plant automation host. (Compl. p. 6).

IV. Analysis of Infringement Allegations

’893 Patent Infringement Allegations

Claim Element (from Independent Claim 30)	Alleged Infringing Functionality	Complaint Citation	Patent Citation
receiving, using one or more processors configured by software within one or more modules, a parameter of a circuit;	The Product practices this step by using processors to receive a parameter of a circuit, for example in WirelessHART systems that target sensors and actuators.	¶15	col. 12:5-7
comparing, using the one or more configured processors, a digital value, which corresponds to a magnitude of the parameter of the circuit, to a plurality of threshold values wherein the plurality of threshold values define a respective plurality of ranges of digital values, each range corresponding to one of a plurality of conditions of the circuit including a normal condition and at least one alarm condition;	The Product compares measured values to configured digital values in memory. Process alerts can be set for variables, and an alert is sent when the data point is exceeded.	¶16	col. 12:1-11
assigning, using the one or more configured processors, a status according to the digital value being within a particular range defined by one or more of the plurality of threshold values; and	Alarm configurations (e.g., HI HI, HI, LO, LO LO) are alleged to indicate the assignment of a status based on the measured digital value falling within a particular range.	¶17	col. 12:12-17
transmitting, using a transmitter, the status to a central monitoring system.	WirelessHART devices are alleged to communicate status over a wireless network to a remote computing system, which functions as a central monitoring system.	¶18	col. 12:18-20

• Identified Points of Contention:
  • Scope Questions: The infringement analysis may turn on the scope of the term "a parameter of a circuit." The patent specification heavily emphasizes monitoring electrical resistance in security circuits. The complaint alleges infringement by devices monitoring physical process variables like pressure and temperature. A central question will be whether "a parameter of a circuit" can be construed to encompass measurements of physical phenomena external to the monitoring device's own electrical circuit.
  • Technical Questions: What evidence demonstrates that the accused products' general-purpose process alerts (e.g., a high-temperature warning) function as the specific "status" assignment claimed in the patent? The court may need to distinguish between reporting a measurement from an external process and reporting on the operational state or integrity of the electrical monitoring circuit itself, as depicted in the patent's embodiments (e.g., 'open circuit', 'short circuit'). (’893 Patent, FIG. 4).

V. Key Claim Terms for Construction

• The Term: "a parameter of a circuit"

  • Context and Importance: The viability of the infringement case hinges on the construction of this term. A narrow construction limited to intrinsic electrical properties of a circuit (e.g., resistance) could present a significant challenge to the Plaintiff's theory, which is based on the monitoring of physical process variables (e.g., temperature).
  • Intrinsic Evidence for a Broader Interpretation: Asserted claim 30 uses the general term "a parameter," which is facially broader than the term "measured electrical parameter" used in other claims like claim 1. This distinction may support an argument that "parameter" was not intended to be limited to only electrical properties. (’893 Patent, col. 9:18, col. 12:6).
  • Intrinsic Evidence for a Narrower Interpretation: The specification, including the abstract and detailed description of the preferred embodiments, overwhelmingly describes the invention in the context of measuring circuit resistance to determine the status of switches in a security system. (’893 Patent, Abstract; col. 2:10-17; FIG. 4). This focus could be used to argue that the scope of the invention is limited to monitoring such electrical parameters.

• The Term: "status"

  • Context and Importance: Practitioners may focus on this term because the patent's examples of "status" relate to the electrical integrity of the monitored line (e.g., "Normal," "Open Circuit," "Short Circuit"). The complaint, however, equates this with alerts about external physical conditions ("HI HI Alarm" for pressure). The definition of "status" will determine if these are equivalent for infringement purposes.
  • Intrinsic Evidence for a Broader Interpretation: The claim language "assign a status based on the digital value being within a particular range" does not, on its face, restrict what the "status" represents, so long as it is derived from the comparison. (’893 Patent, col. 12:13-17).
  • Intrinsic Evidence for a Narrower Interpretation: The patent’s only specific examples define "status" in terms of the circuit's electrical condition. Figure 4 explicitly lists "SHORT CIRCUIT," "NORMAL," "ALARM," and "OPEN CIRCUIT" as the possible statuses derived from an A/D count corresponding to resistance. (’893 Patent, col. 4:46-51, FIG. 4). This may support an interpretation that "status" refers to the operational condition of the monitoring circuit itself, not an external process.

VI. Other Allegations

• Indirect Infringement: The complaint alleges that Defendant induces infringement by encouraging the use of the accused devices through "distribution, support and customer services." (Compl. ¶12).

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

• A core issue will be one of definitional scope: Can the term "a parameter of a circuit", which is rooted in the patent's disclosure of monitoring electrical resistance in security systems, be construed to cover physical process variables like temperature and pressure in the accused industrial automation products?
• A key evidentiary question will be one of technical application: Does the accused products' system for reporting alerts on external process conditions (e.g., a "high temperature" alert) constitute the specific method of "assigning a status" to a circuit parameter as claimed, or is there a fundamental mismatch between monitoring an external physical phenomenon and monitoring the electrical integrity of the circuit itself as described in the patent?