Natus Medical Inc v. Nox Medical Ehf

1. Case Identification

• Case #: IPR2016-01822
• Patent #: 9,059,532
• Filed: September 15, 2016
• Petitioner(s): Natus Medical Inc., Natus Neurology Inc., Embla Systems LLC, and Embla Systems Ltd.
• Patent Owner(s): Nox Medical EHF.
• Challenged Claims: 1-9 and 13

2. Patent Overview

• Title: Electrode Belt Connector
• Brief Description: The ’532 patent relates to a connector for electrically coupling a biometric electrode belt to a monitoring device, particularly for applications such as respiratory inductance plethysmography. The claimed invention is a molded plastic connector frame featuring a receiving hole with a slot, configured to function as a female snap fastener, where a conductor from the belt wraps around an adjacent engaging member to establish electrical contact with a male snap protrusion.

3. Grounds for Unpatentability

Ground 1: Anticipation by Hermannsson - Claims 1-3, 6-9, and 13 are anticipated by Hermannsson under 35 U.S.C. § 102.

• Prior Art Relied Upon: Hermannsson (Patent 8,025,539).
• Core Argument for this Ground:
  • Prior Art Mapping: Petitioner argued that Hermannsson, a reference not considered during prosecution, disclosed every limitation of the challenged claims. Hermannsson teaches a plastic electrode belt connector with a receiving hole that functions as a female snap fastener for a male snap protrusion. Petitioner asserted that the use of conventional plastics for the connector body inherently provides the claimed "radial flexibility." Hermannsson further discloses a slot extending from the receiving hole to give it a "keyhole-like shape," a conductor (wire loop) that wraps around an adjacent engaging member (extending ridge and wings), and a fastener (teeth) to secure the frame to the electrode belt.
  • Key Aspects: Petitioner emphasized that Hermannsson was improperly excluded as prior art during original prosecution due to a mistaken assumption of common inventorship with the ’532 patent application. A post-issuance certificate of correction changed the inventorship of the ’532 patent, breaking this unity and making Hermannsson valid prior art under §102(e).

Ground 2: Obviousness over McIntire and Hermannsson - Claims 1-9 and 13 are obvious over McIntire in view of Hermannsson.

• Prior Art Relied Upon: McIntire (Patent 8,251,736) and Hermannsson (’539 patent).
• Core Argument for this Ground:
  • Prior Art Mapping: Petitioner contended that McIntire teaches a connector assembly for an electrical lead with a "sufficiently resilient" retention plate having an opening and extending slots that function as a snap-fit connection, meeting the core limitations of the claim 1 frame and flexible receiving hole. To the extent McIntire does not explicitly teach an electrode belt or a specific fastener for attaching the frame to the belt, Hermannsson was cited to supply these known features.
  • Motivation to Combine: Petitioner argued a person of ordinary skill in the art (POSITA) would combine these references to create a low-cost, mass-producible, and adjustable electrode belt. McIntire explicitly stated that its teachings "may be used with any system for measuring any physiologic information," which would include the respiratory monitoring belts described in Hermannsson. Combining these compatible and similar connector designs was presented as a predictable combination of known elements.
  • Expectation of Success: A POSITA would have a high expectation of success as the combination involved integrating known features from similar types of electrode connectors to achieve predictable results.

Ground 3: Obviousness over Gobron and Secondary References - Claims 1-3 are obvious over Gobron in view of Williams, Lawrence, or Sommer.

• Prior Art Relied Upon: Gobron (Application # 2007/0167089), Williams (Patent 937,130), Lawrence (Patent 1,001,054), and Sommer (Patent 3,092,759).

• Core Argument for this Ground:

  • Prior Art Mapping: This ground addressed a specific prosecution history argument where the applicant overcame a rejection over Gobron by adding the limitation of a conductor "wrapped around an engaging member." Petitioner argued Gobron taught a keyhole-shaped plastic connector for an ECG unit with inherent flexibility, while the secondary references (Williams, Lawrence, and Sommer) demonstrated that wrapping a conductor around a structure adjacent to a receiving hole was a well-known, fundamental technique for making electrical connections.
  • Motivation to Combine: A POSITA developing a connector like Gobron's would be motivated to incorporate the mature, basic, and reliable connection method taught by Williams et al. to ensure a robust electromechanical connection. This modification was argued to be an obvious design choice to solve a known problem.
  • Expectation of Success: Integrating a well-understood electrical connection technique into a connector design was described as a straightforward modification that would predictably result in a functional connector.

• Additional Grounds: Petitioner asserted additional obviousness challenges based on other combinations. These included using Harhen as a primary reference for a restriction-fit connector body, and further combining primary grounds with references like Kristbjarnarson, Linville, Uehara, Abizaid, and Orewiler to teach conventional features such as flexible textile belts with interwoven conductors and various known belt fastening and adjusting mechanisms (e.g., buckles with teeth).

4. Key Claim Construction Positions

• "flexibility": Petitioner proposed that the broadest reasonable interpretation is "the ability of a part (related to its geometry and material properties) to elastically deform under an applied stress." This construction was central to its argument that a receiving hole made of conventional plastic inherently possesses the claimed "radial flexibility."
• "passing through the receiving hole": Petitioner argued this term should be interpreted as self-evident and without limitation as to the specific direction or extent of passage. This construction allows prior art where a conductor makes the required electrical contact, even if its path is not identical to the patent's embodiment, to be applied to the claims.

5. Relief Requested

• Petitioner requests institution of an inter partes review (IPR) and cancellation of claims 1-9 and 13 of the ’532 patent as unpatentable.