Hot Systems LLC v. San Diego Association Of Governments

I. Executive Summary and Procedural Information

• Parties & Counsel:
  • Plaintiff: Hot Systems, LLC (Nevada)
  • Defendant: San Diego Association Of Governments (California); Neology, Inc. (Delaware)
  • Plaintiff’s Counsel: Rimon P.C.
• Case Identification: 3:26-cv-00738, S.D. Cal., 02/05/2026
• Venue Allegations: Venue is alleged as proper in the Southern District of California because both defendants are alleged to reside in the district and the dispute arose from activities there, including the operation of toll collection systems.
• Core Dispute: Plaintiff alleges that Defendants’ FasTrak Flex switchable toll transponders infringe patents related to radio frequency identification (RFID) devices that incorporate a mechanical switch to change their operational state.
• Technical Context: The technology at issue involves vehicle-mounted RFID transponders used in automated tolling systems, particularly for high-occupancy toll (HOT) lanes where the toll rate varies based on the number of passengers in the vehicle.
• Key Procedural History: The complaint alleges that the asserted patent family has been previously licensed and litigated. It also alleges pre-suit knowledge for both defendants. Notice to SAN DIEGO ASSOCIATION OF GOVERNMENTS is alleged via a "Claim for Damages" form delivered on February 7, 2025. Notice to NEOLOGY, INC. is alleged based on an Information Disclosure Statement it filed in its own patent application on October 24, 2012, which cited a member of the asserted patent family.

Case Timeline

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

U.S. Patent No. 10,810,578

• Patent Identification: U.S. Patent No. 10,810,578, titled “RFID Financial Device Including Mechanical Switch,” issued October 20, 2020.

The Invention Explained

• Problem Addressed: The patent’s background section identifies a security and privacy problem with conventional RFID tags that store personal or confidential data: an unauthorized RFID reader within range can potentially access the information without the user's knowledge or consent (’578 Patent, col. 2:48-54).
• The Patented Solution: The invention provides an RFID device with a user-operable switch that can change the tag's operational state, such as turning it on or off or altering the information it transmits (’578 Patent, abstract). By incorporating a physical control mechanism like a mechanical sliding switch, a user can manually determine when the RFID tag is active and what information it broadcasts, thereby mitigating the risk of unauthorized access (’578 Patent, col. 11:4-16; ’578 Patent, FIG. 4A-4B).
• Technical Importance: This approach gives users direct physical control over their RFID devices, addressing privacy concerns that arose as RFID technology became integrated into everyday items like driver's licenses, passports, and financial cards (’578 Patent, col. 2:40-48).

Key Claims at a Glance

• The complaint asserts independent claim 1 and dependent claims 2-5, 7-11, 13, and 15 Compl. ¶37
• Independent Claim 1 recites the essential elements of:
  • A radio frequency identification (RFID) system comprising:
  • an antenna;
  • a switchable RFID tag configured to operate in both a first ON state and a second ON state, and to transmit different information in the first ON state relative to the second ON state;
  • a mechanical sliding switch configured to change the RFID tag from the first ON state to the second ON state;
  • wherein the antenna transmits the different information via a first RF signal in the first ON state and a second RF signal in the second ON state;
  • wherein the information transmitted in the first ON state indicates that the RFID tag is in the first ON state; and
  • wherein the switchable RFID tag is configured to be mounted on a vehicle.

U.S. Patent No. 11,270,182

• Patent Identification: U.S. Patent No. 11,270,182, titled “RFID Financial Device Including Mechanical Switch,” issued March 8, 2022.

The Invention Explained

• Problem Addressed: Similar to the ’578 Patent, the ’182 Patent addresses the security and privacy risks associated with always-on RFID tags that can be read by any nearby reader (’182 Patent, col. 2:54-61).
• The Patented Solution: The patent describes an RFID system with a mechanical switch that allows a user to control the tag's operational state (’182 Patent, abstract). This provides a manual safeguard against unwanted reading of the tag, giving the user control over when the device can transmit data (’182 Patent, col. 10:1-12).
• Technical Importance: The technology provides a user-centric solution to privacy concerns in RFID applications by adding a physical, intuitive control layer to an otherwise automated communication technology (’182 Patent, col. 2:45-53).

Key Claims at a Glance

• The complaint asserts independent claim 1 and dependent claims 2-11 and 13-21 Compl. ¶49
• Independent Claim 1 recites the essential elements of:
  • A radio frequency identification (RFID) system comprising:
  • an antenna;
  • a switchable RFID tag configured to operate in both a first ON state and a second ON state, and to transmit different information in the first ON state relative to the second ON state;
  • a mechanical switch configured to change the RFID tag from the first ON state to the second ON state;
  • wherein the antenna transmits the different information via a first RF signal in the first ON state and a second RF signal in the second ON state; and
  • wherein the information transmitted in the first ON state indicates that the RFID tag is in the first ON state.

III. The Accused Instrumentality

Product Identification

• The accused products are the "FasTrak Flex" switchable toll transponders and the associated services provided by Defendants Compl. ¶¶5, 18

Functionality and Market Context

• The FasTrak Flex is an identification device used for automated toll collection on SANDAG's toll roads Compl. ¶18 It features a sliding mechanical switch with three settings corresponding to the number of occupants in the vehicle (e.g., 1, 2, or 3+ people) Compl. ¶19 The complaint provides an image of the accused FasTrak Flex transponder, which shows a physical sliding switch with settings for "1 Person", "2 People", and "3+ People" Compl. p. 6 When queried by a toll reader, the transponder transmits different information depending on the switch's position, which allows the tolling system to charge a variable rate or provide a discount Compl. ¶19 This functionality is used for traffic management on high-occupancy toll lanes Compl. ¶20

IV. Analysis of Infringement Allegations

’578 Patent Infringement Allegations

’182 Patent Infringement Allegations

Identified Points of Contention

• Scope Question: The asserted claims recite a device with "a first ON state and a second ON state," whereas the accused product has three distinct operational states Compl. ¶19 The complaint alleges that any two of the three settings correspond to the claimed states Compl. ¶19 This raises the question of whether a three-state device can be found to meet a claim limitation reciting two states.
• Technical Question: The claims require that the transmitted information "indicates that the RFID tag is in the first ON state." The complaint alleges this is met because the toll amount charged is dependent on the signal received by the reader Compl. ¶19 This raises a technical question about the nature of the indication: does the transmission of data that allows a back-end system to infer the device's state satisfy this limitation, or does the claim require the transmitted data itself to contain an explicit status identifier?

V. Key Claim Terms for Construction

The Term: "to transmit different information"

Context and Importance

• The infringement theory rests on the allegation that moving the transponder's switch causes it to "transmit different information" Compl. ¶19 The construction of this term is central to determining if the change in signal between the accused product's settings qualifies as "different information" under the patents.

Intrinsic Evidence for Interpretation

• Evidence for a Broader Interpretation: The patent specification describes using a switch to cause "different information or signals" to be transmitted without specifying the degree of difference required (’578 Patent, col. 4:22-23). This may support an interpretation where any change in the data payload, such as altering a single bit or field, constitutes "different information."
• Evidence for a Narrower Interpretation: Certain embodiments describe using switches to select between entirely different financial accounts or functions (’578 Patent, col. 14:50-57). This context could be used to argue for a narrower construction requiring a more substantial or functionally distinct change in the transmitted information.

The Term: "indicates that the RFID tag is in the first ON state"

Context and Importance

• This term is critical because the complaint's infringement theory relies on an indirect form of indication, where the tolling system infers the state based on which toll to charge Compl. ¶19 Whether this inferential process meets the claim's requirement will be a key issue.

Intrinsic Evidence for Interpretation

• Evidence for a Broader Interpretation: The claims do not specify the format or method of indication. The specification discusses a tag responding with "data indicating a first state" versus a "second state" generally, which may support a broader view that any unique signal corresponding to a state serves to "indicate" it (’578 Patent, col. 10:53-56).
• Evidence for a Narrower Interpretation: The term "indicates" could be construed to require a more direct data representation, such as a dedicated status field within the transmitted data packet. A party might argue that a system requiring an external lookup table to interpret the state from a raw data value does not meet the limitation that the information itself indicates the state.

VI. Other Allegations

Indirect Infringement

• The complaint alleges both inducement and contributory infringement against both Defendants Compl. ¶¶39-43 Compl. ¶¶51-55 The allegations are based on Defendants providing the FasTrak Flex transponders to drivers, advertising their use, providing financial incentives (discounts) that require their use, and supplying the toll readers that form the complete infringing system Compl. ¶40 Compl. ¶52

Willful Infringement

• Willfulness is alleged based on pre-suit knowledge of the patents or patent family.
  • For SANDAG, knowledge is alleged from at least February 7, 2025, based on a hand-delivered "Claim for Damages" Compl. ¶21 Compl. ¶24
  • For NEOLOGY, knowledge of the patent family is alleged from as early as October 24, 2012, based on an Information Disclosure Statement citing a related patent, with knowledge of the asserted patents specifically alleged from at least August 21, 2025 Compl. ¶25 Compl. ¶26

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

• A core issue will be one of definitional scope: can the claim language "a first ON state and a second ON state" be construed to read on an accused device that operates in three distinct states? The case may turn on whether the use of any two of those three states is sufficient to meet the claim limitation as a matter of law.
• A key evidentiary question will be one of technical function: does the accused transponder's transmission of different data, which allows a remote system to infer the transponder's setting, satisfy the claim requirement that the transmitted information itself "indicates" the state of the tag?
• A central question for willfulness and damages, particularly concerning Defendant NEOLOGY, will be the sufficiency of notice: does a 2012 Information Disclosure Statement citing a patent in the same family provide the requisite pre-suit knowledge of the specific, later-issued patents asserted in this case?