American National Mfg Inc v. Sleep Number Corp

1. Case Identification

• Case #: IPR2019-00514
• Patent #: 5,904,172
• Filed: December 29, 2018
• Petitioner(s): American National Manufacturing Inc.
• Patent Owner(s): Select Comfort Corporation
• Challenged Claims: 2, 4, 6, 12, 16, 22, and 24

2. Patent Overview

• Title: Valve Enclosure Assembly for Air Mattresses
• Brief Description: The ’172 patent (referred to as Gifft) discloses a valve enclosure assembly for controlling the pressure in an inflatable mattress. The invention purports to improve on prior art by providing a new solenoid-actuated valve design and a tap on the valve enclosure to allow for continuous pressure monitoring, aiming to reduce air leaks and improve manufacturing efficiency.

3. Key Claim Construction Positions

• Petitioner argued that the means-plus-function term “pressure monitor means” (PMM), subject to pre-AIA 35 U.S.C. §112, ¶6, required construction. Based on different embodiments disclosed in the ’172 patent, Petitioner proposed three constructions critical to its unpatentability arguments:
  • PMM1 (General Construction): Proposed for infringement contentions. Function: continuously monitoring pressure in at least one bladder. Structure: a port fluidly coupled to the interior of the valve enclosure assembly, a pressure sensor, and a tube connecting the port to the sensor.
  • PMM2 (for claims 2, 6): An alternative construction where the PMM does not specify communication with a valve. Function: continuously monitoring pressure in the bladder. Structure: a port on the enclosure fluidly coupled to the interior of the valve enclosure assembly, a pressure sensor, and a connecting tube.
  • PMM3 (for claims 12, 16): An alternative construction where the PMM specifies communication with a valve. Function: monitoring pressure in the bladder. Structure: a port on the valve itself that is fluidly coupled to the valve, a pressure sensor, and a connecting tube.

4. Grounds for Unpatentability

Ground 1: Anticipation of Claims 2, 12, and 22 - Claims are unpatentable under 35 U.S.C. §102(b) as anticipated by Shafer.

• Prior Art Relied Upon: Shafer (WO 96/13947).
• Core Argument for this Ground:
  • Prior Art Mapping: Petitioner argued that Shafer, which was not considered during prosecution, teaches every element of these claims. Shafer discloses an air control system for an air bed with an “air distribution unit 206” that Petitioner mapped to the claimed “valve enclosure assembly.” This unit contains solenoid valves (338, 340) operated by a processor (162) to control air pressure in bladders. Petitioner contended that Shafer's "solenoid retaining resilient fingers 331" and snap-fit portions function as the claimed “plurality of guides and stops” for positioning components. Crucially, Petitioner asserted that Shafer's pressure sensors (156, 158) connected to air outlets (334, 336) anticipate the “pressure monitor means” limitation by continuously monitoring bladder pressure, consistent with the PMM1 construction.

Ground 2: Obviousness of Claims 6, 16, 20, and 24 - Claims are obvious over Shafer in view of Grant.

• Prior Art Relied Upon: Shafer (WO 96/13947) and Grant (Patent 5,353,838).
• Core Argument for this Ground:
  • Prior Art Mapping: This ground addresses claims requiring a two-part enclosure with a flexible seal. Petitioner relied on Shafer for the base system as in Ground 1. Grant, also in the field of air bed pumps, was introduced to teach a two-part enclosure (base 26 and cover 30) that is hermetically sealed using a flexible O-ring (34).
  • Motivation to Combine: Petitioner asserted a person of ordinary skill in the art (POSITA) would combine Grant’s O-ring sealed, two-part enclosure with Shafer’s system. Shafer itself identified noise and vibration dampening as advantageous, and Grant discloses its sealed, two-part enclosure as a solution for minimizing noise. A POSITA would combine the references to gain the benefits of improved assembly, serviceability, and noise reduction.
  • Expectation of Success: The combination would have been a predictable substitution of a well-known sealing method (an O-ring) for the chemical bonding used in Shafer. A POSITA would have had a high expectation of success, as Grant's O-ring would be expected to perform its conventional sealing function effectively within Shafer's enclosure.

Ground 3: Obviousness of Claim 2 - Claim 2 is obvious over Shafer in view of Kashiwamura.

• Prior Art Relied Upon: Shafer (WO 96/13947) and Kashiwamura (Patent 4,655,505).
• Core Argument for this Ground:
  • Prior Art Mapping: This ground presents an alternative obviousness theory for claim 2, focused on a different configuration of the pressure monitoring system. Shafer again supplied the foundational system. Kashiwamura, which teaches pneumatic controls for air bags in a vehicle seat, was cited for its disclosure of a single pressure sensor (28) located in a common conduit (26) upstream of the individual solenoid valves.
  • Motivation to Combine: A POSITA would combine Kashiwamura’s single-sensor design with Shafer's system to simplify the design and reduce costs. Kashiwamura explicitly teaches that using one common sensor simplifies the pressure control system, enhances reliability, and reduces cost compared to systems with multiple sensors.
  • Expectation of Success: Implementing Kashiwamura's pressure monitoring system in Shafer's device would be a straightforward application of known engineering principles. The single-sensor system would be expected to retain its function of accurately measuring pressure in a fluidly sealed valve unit with multiple valved outlets.
• Additional Grounds: Petitioner asserted numerous additional grounds, including anticipation of all challenged claims by Vrzalik (Patent 5,044,029) and various other obviousness combinations primarily leveraging Shafer with other references like Dye (Patent 5,383,894), Cammack (Patent 4,309,783), and Ramacier (Patent 5,494,074) to teach specific features such as alternative valve monitoring configurations and snap-fit valve arrangements.

5. Relief Requested

• Petitioner requested institution of an inter partes review and cancellation of claims 2, 4, 6, 12, 16, 22, and 24 of Patent 5,904,172 as unpatentable.