PTAB

IPR2016-00136

South Tek Systems LLC v. Engineered Corrosion Solutions LLC

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Petition
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1. Case Identification

2. Patent Overview

  • Title: Fire Protection System Having Reduced Corrosion
  • Brief Description: The ’700 patent relates to using nitrogen gas, supplied by a nitrogen generator, to replace the compressed air typically used to pressurize dry pipe fire protection sprinkler systems. Displacing oxygen with nitrogen is intended to inhibit corrosion within the system's piping network.

3. Grounds for Unpatentability

Ground 1: Claims 1-2 and 5-9 are obvious over Viking in view of Wood and Applicant Admitted Prior Art (AAPA)

  • Prior Art Relied Upon: Viking (a 2007 technical data sheet), Wood (Patent 6,540,028), and AAPA.
  • Core Argument for this Ground:
    • Prior Art Mapping: Petitioner argued that Viking, a reference not considered during prosecution, disclosed all elements of a conventional dry pipe sprinkler system as claimed, including the explicit teaching that the system piping can be filled with "pressurized air or nitrogen." The only element not expressly taught by Viking was sourcing the nitrogen from a "nitrogen generator." However, Petitioner asserted that the ’700 patent’s own specification (AAPA) admitted that nitrogen generators were well-known and commercially available for this purpose. For the claimed "vent," Petitioner pointed to Wood, which disclosed an automatic condensate drain that functions as a pressure-operated vent, allowing gas to exit while maintaining sufficient system pressure to keep the main valve closed. Petitioner contended that the claimed benefit of reduced corrosion is an inherent and obvious result of displacing oxygen with nitrogen.
    • Motivation to Combine: A person of ordinary skill in the art (POSITA), aware of the corrosion problems in dry pipe systems and Viking’s suggestion to use nitrogen, would be motivated to employ a well-known nitrogen generator (AAPA) as the most logical source for that nitrogen. To implement a nitrogen purging process, a POSITA would find it obvious to incorporate a pressure-maintaining vent, such as the one taught by Wood, to allow displaced ambient air to exit without compromising system integrity.
    • Expectation of Success: A POSITA would have a reasonable expectation of success because combining these elements involved using known components (Viking's system, a nitrogen generator, Wood's vent) for their known functions, yielding the predictable result of a corrosion-resistant sprinkler system.

Ground 2: Claims 3-4 are obvious over Viking, Wood, and AAPA, further in view of Wagner

  • Prior Art Relied Upon: Viking (a 2007 technical data sheet), Wood (Patent 6,540,028), AAPA, and Wagner (Patent 7,717,776).

  • Core Argument for this Ground:

    • Prior Art Mapping: This ground incorporated the arguments from Ground 1 and added Wagner to address the limitations of claims 3 and 4, which required an "oxygen sensor" and configuring the nitrogen generator to operate "in response to an oxygen level measured by the oxygen sensor." Petitioner asserted that Wagner taught a system for preventing fire in a room by using a nitrogen generator in conjunction with oxygen sensors to measure and control the oxygen concentration. Wagner's system was configured to automatically activate the nitrogen generator to maintain a desired low-oxygen atmosphere.
    • Motivation to Combine: A POSITA seeking to optimize the nitrogen-purged sprinkler system of Ground 1 would be motivated to add a control mechanism to ensure the desired oxygen level is achieved and maintained efficiently. Wagner provided a known and logical solution: incorporating an oxygen sensor and a controller to automate the operation of the nitrogen generator. This would improve system performance and reliability, providing a clear motivation for the combination.
    • Expectation of Success: The integration of Wagner’s sensor and control loop into the system of Ground 1 was presented as a straightforward application of conventional automation and process control principles, which a POSITA would expect to implement successfully.

  • Additional Grounds: Petitioner asserted additional obviousness challenges (Grounds 3 and 4) based on the combination of Wood, Ringer (Patent 7,322,423), and Wagner. This combination was similar to one formulated by the examiner during prosecution, which Petitioner argued should have been maintained.

4. Key Claim Construction Positions

  • "drum drip": Petitioner argued that this term, added via amendment to secure allowance of the claims, was the critical point of novelty identified by the examiner. As the intrinsic evidence provided no clear definition, Petitioner asserted, based on extrinsic evidence (Loiacono, Patent 4,849,739), that "drum drip" is a well-known term of art for a "condensate drain." This construction was central to Petitioner's argument because primary prior art references like Wood disclosed a "condensate drain," which would inherently teach the "drum drip" limitation under this construction. Petitioner argued the examiner erred by not properly construing the term and recognizing it was already present in the prior art of record.

5. Relief Requested

  • Petitioner requested the institution of an inter partes review and the cancellation of claims 1-9 of the ’700 patent as unpatentable.