Sotera Wireless Inc v. Masimo Corp

1. Case Identification

• Case #: IPR2020-01078
• Patent #: RE47,218
• Filed: June 11, 2020
• Petitioner(s): Sotera Wireless, Inc.; Hon Hai Precision Industry Co., Ltd. (as real party-in-interest)
• Patent Owner(s): Masimo Corporation
• Challenged Claims: 1-10 and 12-18

2. Patent Overview

• Title: Adaptive Alarm System
• Brief Description: The ’218 patent describes a medical monitoring system designed to reduce clinically insignificant electronic alarms. The system uses a patient's physiological data, such as oxygen saturation (SpO2) from a pulse oximeter, to dynamically access and apply alarm thresholds that adapt to the patient's changing condition.

3. Grounds for Unpatentability

Ground 1: Obviousness over Bock in view of Kiani - Claims 1-4, 7, and 12-15 are obvious over Bock in view of Kiani.

• Prior Art Relied Upon: Bock (Patent 7,079,035) and Kiani (Patent 6,597,933).
• Core Argument for this Ground:
  • Prior Art Mapping: Petitioner asserted that Bock taught nearly all limitations of a system for reducing alarms by dynamically adjusting thresholds based on patient data. Bock disclosed monitoring a physiological parameter, comparing it to a first threshold (a "tracking threshold"), and then adjusting that threshold to create a second, replacement threshold if the parameter crossed the first. Petitioner argued Bock's method of setting the tracking threshold—for example, as a percentage difference from a "calculated representative value"—satisfied the key claim limitation of an offset that diminishes as the patient’s measured value approaches a lower limit (Bock’s "extremity limit"). Kiani was cited to supply the explicit teaching of a conventional optical pulse oximeter, which measures SpO2 by transmitting optical radiation into tissue. Petitioner contended that while Bock taught monitoring SpO2, Kiani provided the well-known and standard hardware for doing so.
  • Motivation to Combine (for §103 grounds): A person of ordinary skill in the art (PHOSITA) would combine Kiani’s standard optical sensor with Bock’s alarm system to implement the SpO2 monitoring that Bock’s system was designed for. Using a non-invasive optical sensor as taught by Kiani was the conventional and predictable method for measuring SpO2, making it a simple substitution of one known element for another to achieve a predictable result.
  • Expectation of Success (for §103 grounds): A PHOSITA would have a high expectation of success, as integrating a standard SpO2 sensor into a monitoring system’s alarm logic was a routine and well-understood task.

Ground 2: Obviousness over Bock, Woehrle, and Kiani - Claims 5-6, 8-10, and 16-18 are obvious over Bock, Woehrle, and Kiani.

• Prior Art Relied Upon: Bock (Patent 7,079,035), Woehrle (WO 2009/093159), and Kiani (Patent 6,597,933).
• Core Argument for this Ground:
  • Prior Art Mapping: This ground built upon the combination of Bock and Kiani to address the remaining claims, which introduced a time delay before triggering an alarm. Petitioner argued that Woehrle disclosed this missing element. Woehrle taught an alarm system for medical instruments that determined an alarm delay based on the degree of deviation of a physiological parameter from a normal value. Specifically, Woehrle taught that the time delay should decrease as the patient’s condition worsens (i.e., as the measured value gets closer to a predefined limit). This teaching directly mapped to the limitations of claims 5, 6, and 8, which required a time delay that is a function of the alarm threshold and decreases as the patient's measurement approaches a lower limit.
  • Motivation to Combine (for §103 grounds): A PHOSITA would combine Woehrle’s teachings with the Bock/Kiani system because both Bock and Woehrle addressed the same well-known problem of reducing nuisance alarms in patient monitoring. Woehrle’s use of an intelligent time delay was a known technique to improve alarm specificity. A PHOSITA would have been motivated to add this feature to Bock's dynamic threshold system to create a more robust solution that attacked the false alarm problem from two different, complementary angles, leading to the predictable result of further reducing nuisance alarms.
  • Expectation of Success (for §103 grounds): Combining a known time delay technique with a known dynamic thresholding system was a straightforward design choice that would have been expected to work as intended.

4. Arguments Regarding Discretionary Denial

• Petitioner argued against discretionary denial under 35 U.S.C. §325(d) because the core prior art and arguments were not previously before the U.S. Patent and Trademark Office. The primary references, Bock and Woehrle, were not cited or considered during the original prosecution or reissue. While Kiani was listed in a large Information Disclosure Statement (IDS), it was not substantively analyzed or used as a basis for rejection by the examiner, and thus the combination presented in the petition was new.

5. Relief Requested

• Petitioner requests institution of an inter partes review (IPR) and cancellation of claims 1-10 and 12-18 of the ’218 patent as unpatentable.