Google LLC v. EcoFactor Inc

1. Case Identification

• Case #: IPR2021-00409
• Patent #: 8,412,488
• Filed: January 11, 2021
• Petitioner(s): Google LLC
• Patent Owner(s): EcoFactor, Inc.
• Challenged Claims: 1-16

2. Patent Overview

• Title: Monitoring HVAC System Operational Status
• Brief Description: The ’488 patent discloses a system for monitoring the operational status of a heating, ventilation, and air conditioning (HVAC) system. The system infers whether the HVAC system is on or off by deriving an estimation for the rate of change of a structure's inside temperature in response to the outside temperature, and then comparing that estimation to the actual, recorded inside temperature.

3. Grounds for Unpatentability

Ground 1: Obviousness over Ehlers and Van Ostrand - Claims 1, 3-9, and 11-16 are obvious over Ehlers in view of Van Ostrand.

• Prior Art Relied Upon: Ehlers (Application # 2004/0117330) and Van Ostrand (Application # 2005/0159846).
• Core Argument for this Ground:
  • Prior Art Mapping: Petitioner argued that Ehlers taught a system for monitoring an HVAC system that includes processors, receives inside and outside temperature measurements, and compares these measurements over time to derive a "thermal gain rate"—an estimation of the rate of change in inside temperature in response to outside temperature. This was alleged to meet most limitations of independent claims 1 and 9. Petitioner asserted that Van Ostrand supplied the final limitation: comparing an inside temperature with an estimation for the rate of change to determine if the HVAC system is on or off. Van Ostrand expressly taught monitoring the rate of change in room temperature to infer whether an HVAC component is operating or has failed, either by comparing rates of change before and after activation or by comparing an actual rate of change to a learned (expected) rate of change.
  • Motivation to Combine: Petitioner presented two independent motivations. First, a POSITA would combine the references to improve the HVAC health monitoring taught by Ehlers with the specific rate-of-change diagnostic technique from Van Ostrand. Second, a POSITA would use Van Ostrand’s technique to provide a low-cost, reliable method for verifying customer compliance with demand reduction requests—a known problem and a feature of the Ehlers system.
  • Expectation of Success: Petitioner asserted that the art of building energy management was predictable, and a POSITA would have had a reasonable expectation of success in combining the known techniques to solve the known problem of HVAC status verification.
  • Key Aspects: Petitioner argued that Van Ostrand supplied the key teaching that the Examiner found missing from the prior art during the original prosecution of the ’488 patent, and therefore discretionary denial under §325(d) would be inappropriate.

Ground 2: Obviousness over Ehlers, Van Ostrand, and Rosen - Claims 2 and 10 are obvious over Ehlers in view of Van Ostrand and further in view of Rosen.

• Prior Art Relied Upon: Ehlers (Application # 2004/0117330), Van Ostrand (Application # 2005/0159846), and Rosen (Patent 6,789,739).
• Core Argument for this Ground:
  • Prior Art Mapping: This ground built upon the combination in Ground 1 to address the limitations of claims 2 and 10, which require receiving outside temperature measurements for geographic regions based on ZIP codes. Petitioner argued that while Ehlers taught receiving "local weather forecast" data from an external source, it did not specify the method for localizing that data. Rosen was introduced because it taught a thermostat system that receives location-specific weather data from an internet service by providing the structure's ZIP code.
  • Motivation to Combine: A POSITA seeking to implement Ehlers's teaching of receiving "local" weather data would have looked to known, common methods for localizing such information. Petitioner contended that using a ZIP code, as taught by Rosen, was a simple, well-known, and obvious way to implement this feature in the Ehlers system.
  • Expectation of Success: Integrating the use of a common identifier like a ZIP code into the Ehlers system to retrieve weather data was presented as a straightforward modification with a high expectation of success.

4. Key Claim Construction Positions

• "rate of change in inside temperature": The petition noted the district court construed this term as "the difference between inside temperature measurements divided by the span of time between the measurements." This construction was central to mapping the "thermal gain rate" of Ehlers and the temperature "slope" of Van Ostrand to the claim language.
• "compare(s)": The petition relied on the agreed-upon construction from co-pending litigation: "analyze to determine one or more similarities or differences between." This construction was used to argue that Ehlers’s derivation of a thermal gain rate and Van Ostrand’s analysis of temperature slopes met the "comparing" limitations of the claims.

5. Arguments Regarding Discretionary Denial

• Petitioner argued that the Board should decline to exercise discretionary denial under Fintiv for several reasons. First, co-pending litigation against the Petitioner was subject to a motion to stay pending a motion to transfer venue. Second, the trial in the co-pending litigation was not scheduled until December 2021 and was subject to further delay, with claim narrowing not required until September 2021. Third, Petitioner stipulated that, if IPR is instituted, it would not pursue the same invalidity grounds in the district court, mitigating concerns of duplicative efforts. Finally, Petitioner asserted the merits of the petition were strong.

6. Relief Requested

• Petitioner requests institution of an inter partes review and cancellation of claims 1-16 of the ’488 patent as unpatentable.