DCT
0:05-cv-00756
Global Traffic Tech LLC v. Tomar Electronics Inc
I. Executive Summary and Procedural Information
- Parties & Counsel:
- Plaintiff: 3M Innovative Properties Company and 3M Company (Delaware)
- Defendant: TOMAR Electronics, Inc. (Arizona)
- Plaintiff’s Counsel: Crawford Maunu PLLC; Faegre & Benson LLP
- Case Identification: 0:05-cv-00756, D. Minn., 04/13/2005
- Venue Allegations: Venue is alleged to be proper based on Defendant transacting business in Minnesota and committing acts that caused injury to the Plaintiffs within the district.
- Core Dispute: Plaintiff alleges that Defendant’s Strobecom II optical traffic preemption products infringe a patent related to embedding data within a priority-based optical signal.
- Technical Context: The technology involves systems that allow authorized vehicles, such as emergency responders or mass transit, to remotely control traffic signals by transmitting encoded optical pulses.
- Key Procedural History: The complaint identifies 3M Innovative Properties Company as the patent owner by assignment and 3M Company as the exclusive licensee. No other significant procedural events are mentioned.
Case Timeline
| Date | Event |
|---|---|
| 1991-10-24 | U.S. Patent No. 5,172,113 Priority Date (Filing Date) |
| 1992-12-15 | U.S. Patent No. 5,172,113 Issues |
| 2005-04-13 | Complaint Filed |
II. Technology and Patent(s)-in-Suit Analysis
U.S. Patent No. 5,172,113 - "System and Method for Transmitting Data in an Optical Traffic Preemption System," issued December 15, 1992
The Invention Explained
- Problem Addressed: The patent describes prior art optical traffic preemption systems as being limited in their ability to convey information. While they could signal different priority levels using distinct pulse repetition rates (e.g., 10 pulses/sec for low priority vs. 14 pulses/sec for high priority), they could not transmit more complex, variable data, such as a unique vehicle identifier. (’113 Patent, col. 2:22-51). This limited the functionality and security of such systems.
- The Patented Solution: The invention discloses a method and system for transmitting variable data by interleaving "data pulses" into the spaces between the existing "priority pulses" of an optical signal (’113 Patent, Abstract). This approach allows a data-rich signal to be transmitted while maintaining backward compatibility with older receivers designed to detect only the priority pulse rate (’113 Patent, col. 7:58 - col. 8:8; Fig. 3). The encoded data can include vehicle identification codes, operational commands for the traffic controller, or system configuration parameters (’113 Patent, col. 3:40-62).
- Technical Importance: This method created a "third tier of signal discrimination," moving beyond simple priority levels to enable the transmission of rich, variable data, which supported new applications like vehicle-specific logging, advanced mass transit scheduling, and more secure access control. (’113 Patent, col. 5:36-41).
Key Claims at a Glance
- The complaint alleges infringement of the "claims of the ‘113 patent" without specifying any particular claims (Compl. ¶10). Analysis will focus on independent claim 1, which describes the core method of the invention.
- The essential elements of independent claim 1 include:
- emitting a stream of light pulses which include priority pulses occurring at a repetition rate and data pulses interleaved with the priority pulses...
- receiving the stream of light pulses;
- producing a received signal that represents the stream of light pulses;
- identifying received light pulses that are separated from one another by one of n predetermined time intervals;
- sorting data pulses from priority pulses based on the predetermined time intervals...; and
- assembling data derived from the priority pulses, the data pulses and the predetermined time intervals.
- The complaint does not explicitly reserve the right to assert dependent claims.
III. The Accused Instrumentality
Product Identification
The complaint identifies "TOMAR's products sold under or in connection with the name Strobecom II." (Compl. ¶10).
Functionality and Market Context
The complaint alleges that the Strobecom II products are used for optical traffic preemption but does not provide specific technical details about their operation, features, or signal structure. (Compl. ¶10). No probative visual evidence provided in complaint.
IV. Analysis of Infringement Allegations
The complaint makes a general allegation of infringement without providing a detailed, element-by-element mapping of the accused product's functionality to the patent's claims.
’113 Patent Infringement Allegations
| Claim Element (from Independent Claim 1) | Alleged Infringing Functionality | Complaint Citation | Patent Citation |
|---|---|---|---|
| emitting a stream of light pulses which include priority pulses occurring at a repetition rate and data pulses interleaved with the priority pulses... | The complaint alleges that the Strobecom II system performs this step but does not describe the specific structure of its optical signal. | ¶10 | col. 7:58-68 |
| receiving the stream of light pulses | The complaint alleges that the Strobecom II system performs this step but provides no details on its receiver components. | ¶10 | col. 10:16-23 |
| producing a received signal that represents the stream of light pulses | The complaint alleges that the Strobecom II system performs this step but does not describe its internal signal processing. | ¶10 | col. 10:31-37 |
| identifying received light pulses that are separated from one another by one of the n predetermined time intervals | The complaint alleges that the Strobecom II system performs this step but does not specify the timing analysis it employs. | ¶10 | col. 11:15-21 |
| sorting data pulses from priority pulses based on the predetermined time intervals separating identified light pulses | The complaint alleges that the Strobecom II system performs this step but does not detail how it differentiates pulse types. | ¶10 | col. 13:12-17 |
| assembling data derived from the priority pulses, the data pulses and the predetermined time intervals | The complaint alleges that the Strobecom II system performs this step but does not explain what data, if any, is assembled. | ¶10 | col. 14:6-12 |
Identified Points of Contention
- Technical Questions: A central question for the court will be evidentiary. What evidence will Plaintiff present to demonstrate that the Strobecom II system's optical signal contains both "priority pulses" and "data pulses" as those terms are used in the patent? The case will depend on a technical analysis of the accused product's signaling protocol.
- Scope Questions: Given the lack of technical detail in the complaint, a dispute over the meaning and scope of the claim terms is foreseeable. For instance, the parties may dispute whether the accused product's signal, even if it contains data, is truly "interleaved" in the manner required by the claim.
V. Key Claim Terms for Construction
The complaint does not provide sufficient detail for analysis of specific claim construction disputes. However, based on the technology, certain terms are likely to be central.
- The Term: "data pulses interleaved with the priority pulses"
- Context and Importance: This phrase captures the core inventive concept. The entire infringement analysis for claim 1 will depend on whether the accused Strobecom II signal can be properly characterized by this structure. The definition of "priority pulse," "data pulse," and "interleaved" will be critical.
- Intrinsic Evidence for Interpretation:
- Evidence for a Broader Interpretation: The patent's summary describes the invention as a method where "data pulses interleaved with the priority pulses is used to transmit variable data." (’113 Patent, col. 3:32-35). A party could argue this language supports a construction covering any format that mixes a basic timing/priority signal with additional information-carrying signals in the intervening periods.
- Evidence for a Narrower Interpretation: The detailed description discloses a specific data packet format comprising a "framing segment," a "start segment," and a "data segment." (’113 Patent, col. 8:28-46). A party could argue that the claims should be limited to this more structured embodiment, potentially excluding other data transmission protocols that do not share this specific format.
VI. Other Allegations
- Indirect Infringement: The complaint makes a conclusory allegation of active inducement and contributory infringement without pleading any specific supporting facts, such as the provision of user manuals or instructions directing infringing use. (Compl. ¶10).
- Willful Infringement: Willfulness is alleged based on "information and belief," with the assertion that Defendant’s infringement occurs with "knowledge of the ‘113 patent." (Compl. ¶11). The complaint does not provide a factual basis for this alleged knowledge.
VII. Analyst’s Conclusion: Key Questions for the Case
- A key evidentiary question will be one of technical operation: Can Plaintiff produce evidence, likely through expert analysis and testing, demonstrating that the Tomar Strobecom II signal protocol practices every step of the asserted method claim, specifically the generation and interpretation of a signal with "data pulses interleaved with the priority pulses"?
- A core issue will be one of definitional scope: How will the court construe the term "interleaved"? The case may turn on whether the term is interpreted broadly to encompass any method of embedding data within a priority signal's timing gaps, or more narrowly to the specific data packet structures and timing intervals described in the ‘113 patent’s preferred embodiments.