Google LLC v. EcoFactor Inc

1. Case Identification

• Case #: IPR2021-01578
• Patent #: 8,886,488
• Filed: September 29, 2021
• Petitioner(s): Google LLC
• Patent Owner(s): EcoFactor, Inc.
• Challenged Claims: 1-15

2. Patent Overview

• Title: System and Method for Calculating Operational Efficiency of an HVAC System
• Brief Description: The ’488 patent discloses a system for improving thermostat functionality by using a server to calculate a building's thermal characteristics and the performance of its heating, ventilation, and air conditioning (HVAC) system. The system calculates a predicted rate of temperature change based on inside/outside temperatures and HVAC status, and compares this to actual measurements to determine operational efficiency.

3. Grounds for Unpatentability

Ground 1: Anticipation of Claims 1, 5-9, and 13-15 by Shah ’927

• Prior Art Relied Upon: Shah ’927 (Patent 5,555,927).
• Core Argument for this Ground:
  • Prior Art Mapping: Petitioner argued that Shah ’927, which describes an HVAC control system that calculates an optimum start time for temperature recovery, discloses every limitation of the challenged independent claims. Central to this argument is the contention that Shah ’927’s calculation of a "thermal time constant" (τ) or a thermal integrity value (ξ) constitutes a "value for the operational efficiency" of an HVAC system, as this term was broadly interpreted by the Patent Owner in co-pending litigation to include time-based metrics. Shah ’927's processor calculates a predicted recovery ramp rate (a rate of change) based on indoor/outdoor temperatures and HVAC status ("ON" cycle), relates this rate to outside temperature, and compares a predicted temperature (Ramp Set Point) with an actual inside temperature to determine when to activate the HVAC system.
  • Key Aspects: This ground relies on the Patent Owner's own proposed broad construction of "operational efficiency" from a parallel proceeding.

Ground 2: Obviousness of Claims 1, 5-9, and 13-15 over Shah ’927 in view of Shah ’233

• Prior Art Relied Upon: Shah ’927 (Patent 5,555,927) and Shah ’233 (Patent 6,478,233).
• Core Argument for this Ground:
  • Prior Art Mapping: This ground was presented as an alternative to Ground 1, applicable under the narrower construction of "operational efficiency" adopted by the International Trade Commission (ITC), defined as "energy required by the HVAC system to change inside temperature by a given amount over a given time." Petitioner asserted that while Shah ’927 provides the foundational system for calculating temperature ramp rates, Shah ’233 explicitly teaches calculating the "amount of energy required to recover from energy savings set point temperature value." Shah ’233 provides the necessary equations (e.g., Equation 6) to determine this energy amount based on indoor/outdoor conditions, directly corresponding to the ITC's energy-based construction.
  • Motivation to Combine: A POSITA would combine the teachings because Shah ’233 shares the same inventor as Shah ’927 and expressly incorporates Shah ’927 by reference. A POSITA seeking to improve the system of Shah ’927 by adding energy savings calculations would have naturally looked to the inventor’s own subsequent work in Shah ’233, which teaches exactly how to calculate energy consumption for different setback schedules.
  • Expectation of Success: Success was expected because the art was predictable. Shah ’233 provides a clear mathematical framework for calculating energy use based on temperature data already available in the Shah ’927 system, requiring no undue experimentation to implement.

Ground 3: Obviousness of Claims 2, 3, 10, and 11 over Shah ’927 in view of Rosen

• Prior Art Relied Upon: Shah ’927 (Patent 5,555,927) and Rosen (Patent 6,789,739).

• Core Argument for this Ground:

  • Prior Art Mapping: This ground targets dependent claims requiring the receipt of outside temperatures for geographic regions based on ZIP codes (claims 2, 10) and a programmable thermostat that communicates with the Internet (claims 3, 11). Petitioner argued that while Shah ’927 teaches a programmable thermostat with an on-site outdoor temperature sensor, Rosen teaches a thermostat system that retrieves weather data, including outside temperatures, from a remote source (e.g., a weather website) over the Internet based on the thermostat's location determined by its ZIP code.
  • Motivation to Combine: A POSITA would combine these references to replace the physical outdoor sensor of Shah ’927 with Rosen’s Internet-based weather data retrieval. This modification would be a simple and cost-effective substitution, eliminating the need to install and maintain a physical sensor while leveraging widely available online weather information, a method acknowledged as common in the ’488 patent itself.
  • Expectation of Success: A POSITA would have a high expectation of success in making this simple substitution, as replacing a direct sensor input with a data feed from a known, reliable source like an internet weather service was a well-understood and straightforward design choice in the art.

• Additional Grounds: Petitioner asserted additional obviousness challenges, including combinations using Ehlers ’330 (Application # 2004/0117330) to teach communicating with an HVAC system over a network that includes an electricity meter (for claims 4 and 12).

4. Key Claim Construction Positions

• Petitioner argued that the construction of the term "operational efficiency of a heating, ventilation and air conditioning (HVAC) system" is critical.
  • Under the Patent Owner's broader proposed construction (a time-based metric), Petitioner contended Shah ’927 alone anticipates the claims (Ground 1).
  • Under the ITC's narrower construction ("energy required..."), Petitioner contended the combination of Shah ’927 and Shah ’233 renders the claims obvious (Ground 2), as Shah '233 explicitly adds the "energy required" calculation.

5. Arguments Regarding Discretionary Denial

• Petitioner argued against discretionary denial under Fintiv, asserting that factors weigh in favor of institution.
  • It was argued that all related district court proceedings concerning the ’488 patent are stayed, minimizing any potential overlap or inefficiency.
  • The only co-pending validity challenge is in an ITC investigation, which has a different claim scope at issue and whose validity determinations are not binding on district courts or the PTAB. Therefore, an IPR would not be duplicative and would serve the public interest by conclusively resolving the patentability of all challenged claims.

6. Relief Requested

• Petitioner requests institution of an inter partes review and cancellation of claims 1-15 of the ’488 patent as unpatentable.