Google LLC v. EcoFactor Inc

1. Case Identification

• Case #: IPR2025-00097
• Patent #: 11,835,394
• Filed: November 1, 2024
• Petitioner(s): Google LLC
• Patent Owner(s): EcoFactor, Inc.
• Challenged Claims: 1-18

2. Patent Overview

• Title: Control System for an Environment Inside a Structure
• Brief Description: The ’394 patent relates to HVAC control systems that use a thermostat to maintain a setpoint temperature. The challenged claims concern calculating a current operating profile for the HVAC system and evaluating whether its operational efficiency has decreased over time.

3. Grounds for Unpatentability

Ground 1: Claims 1-3, 5, 10-12, and 14 are obvious over Hildebrand in view of Shah.

• Prior Art Relied Upon: Hildebrand (Patent 5,729,474) and Shah (Patent 5,555,927).
• Core Argument for this Ground:
  • Prior Art Mapping: Petitioner argued that Hildebrand taught the core limitations of a system that anticipates HVAC failure by collecting indoor and outdoor temperatures to calculate and compare operational efficiency values (K values) over time. To the extent Hildebrand’s efficiency metric was not explicitly time-based, Shah taught using a "thermal time constant" (τ), measured in unit time, to form an operating profile and measure operational efficiency for diagnostic purposes. Shah also taught a programmable thermostat.
  • Motivation to Combine: A POSITA would combine Shah’s time-based thermal constant (τ) with Hildebrand’s system to create a more robust efficiency metric, providing predictive diagnostics valid for a greater range of conditions. Petitioner asserted this was a predictable combination of known elements to improve a known system. A POSITA would also have been motivated to use a database for storing and organizing the efficiency data, a common and predictable design choice.
  • Expectation of Success: Petitioner contended a POSITA would have had a high expectation of success because the art was predictable, involving software-based systems with well-known components.

Ground 2: Claims 1-5 and 10-14 are obvious over Hildebrand and Shah in view of Rosen.

• Prior Art Relied Upon: Hildebrand (Patent 5,729,474), Shah (Patent 5,555,927), and Rosen (Patent 6,789,739).
• Core Argument for this Ground:
  • Prior Art Mapping: This ground incorporated the arguments from Ground 1 and added Rosen to address specific claim limitations. Petitioner asserted Rosen taught a programmable thermostat that obtains outside temperatures over the Internet from a weather data provider based on a ZIP code. This addresses limitations requiring receiving "second temperatures" from a "source outside the structure" that is remote from the structure (claims 4 and 13). Rosen also provided another example of a programmable thermostat with a display.
  • Motivation to Combine: A POSITA would combine Rosen’s internet-based weather data with the Hildebrand/Shah system to replace or supplement a physical outdoor sensor. This would reduce the cost, complexity, and potential unreliability associated with installing and maintaining a physical on-site sensor, thereby improving the overall system.
  • Expectation of Success: Petitioner argued success was predictable, as it involved substituting one known data source (a physical sensor) with another known data source (an internet weather service) to achieve a predictable benefit.

Ground 3: Claims 1-3, 5-6, 10-12, and 14-15 are obvious over Hildebrand and Shah in view of Van Ostrand.

• Prior Art Relied Upon: Hildebrand (Patent 5,729,474), Shah (Patent 5,555,927), and Van Ostrand (Application # 2005/0159846).

• Core Argument for this Ground:

  • Prior Art Mapping: Building on Ground 1, this ground added Van Ostrand’s teachings on diagnosing specific HVAC component failures. Petitioner argued that Van Ostrand taught monitoring the rate of temperature change before and after a specific HVAC component or stage is activated. By learning and storing these rates of change as diagnostic profiles, the system could identify which specific component has failed. This mapped to limitations requiring the storage of "diagnostic temperature profiles associated with a plurality of potential defects" (claims 6 and 15).
  • Motivation to Combine: A POSITA would be motivated to integrate Van Ostrand’s diagnostic technique into the Hildebrand/Shah system. While Hildebrand/Shah could detect a general decrease in efficiency, Van Ostrand’s method would provide the significant advantage of pinpointing the specific failing component, enabling more targeted and efficient maintenance.
  • Expectation of Success: Petitioner asserted success was predictable because it involved using a known diagnostic method to improve a known efficiency monitoring system in a predictable way.

• Additional Grounds: Petitioner asserted additional obviousness challenges, including Ground 4 (combining Hildebrand, Shah, Rosen, and Van Ostrand) and Ground 5 (adding McNulty, Application # 2011/0251726, to teach using weather forecasts to predict and modify operating intervals).

4. Key Claim Construction Positions

• "operational efficiency": Petitioner noted that Patent Owner has previously contended this term should be construed as "energy or time to change inside temperature by any given amount for a set of one or more indoor or outdoor conditions." Petitioner applied this apparent understanding in its unpatentability arguments, asserting that the prior art’s use of time-based metrics (like Shah’s thermal time constant) met this construction.

5. Arguments Regarding Discretionary Denial

• §325(d) (Same or Substantially Same Art): Petitioner argued against denial under §325(d), stating that the primary references Hildebrand, Shah, and McNulty were never of record during the prosecution of the ’394 patent. While Rosen and Van Ostrand were of record, they were never cited or applied in a rejection.
• §314(a) (Fintiv Factors): Petitioner argued that the Fintiv factors weigh in favor of institution. It asserted that the co-pending district court litigation is in its very early stages, with no trial date set, no claim construction briefing, and minimal investment by the parties. Petitioner stated its intent to move for a stay if the IPR is instituted and that the petition’s merits are compelling.

6. Relief Requested

• Petitioner requested institution of an inter partes review and cancellation of claims 1-18 of the ’394 patent as unpatentable.