In a significant appellate ruling closed on January 12, 2024, the U.S. Court of Appeals for the Federal Circuit affirmed the patentability of Masimo Corporation’s U.S. Patent No. 10,433,776 B2, covering low power pulse oximetry technology. Apple, Inc. had challenged the patent’s validity through an invalidity/cancellation action—Case No. 22-1891—filed on June 10, 2022. After 581 days of appellate proceedings, the Federal Circuit issued a decisive AFFIRMED judgment, dismissing Apple’s appeal and leaving Masimo’s patent intact.

This ruling carries substantial weight in the wearable health technology sector, where Apple and Masimo have been locked in broad-ranging patent disputes over blood oxygen monitoring features central to the Apple Watch. Patent attorneys, in-house IP counsel, and R&D teams operating in the biosensor and pulse oximetry space must understand the Federal Circuit’s affirmance as a signal that Masimo’s foundational patent portfolio in low power physiological monitoring remains robust—raising serious freedom-to-operate considerations for competing product developers.

Case Overview

The Parties

The Patent at Issue

U.S. Patent No. 10,433,776 B2 covers technology for a low power pulse oximeter—a device that measures blood oxygen saturation and pulse rate using light sensors while consuming minimal battery power. The patent’s key claims relate to managing power consumption in optical physiological monitoring systems, enabling continuous, efficient health tracking in small wearable form factors. This technology is directly relevant to smartwatch and fitness tracker applications where battery life and accurate biosensing must be simultaneously optimized.

• • US10433776B2

Legal Representation

Plaintiff Counsel: Fish & Richardson PC; Wilmer Cutler Pickering Hale & Dorr LLP (lead: Brittany Blueitt Amadi)
Defendant Counsel: Knobbe Martens; Knobbe, Martens, Olson & Bear, LLP (lead: Jarom D. Kesler)

Litigation Timeline & Procedural History

Case No. 22-1891 was filed on June 10, 2022, at the U.S. Court of Appeals for the Federal Circuit—the sole appellate court with jurisdiction over patent matters arising from U.S. district courts and the USPTO. The appeal arose from an invalidity/cancellation action, indicating that the underlying patentability challenge likely originated from an inter partes review (IPR) or similar USPTO proceeding before reaching the Federal Circuit, making this an administrative patent validity dispute rather than a direct district court infringement case. The Federal Circuit’s role here was to review whether the lower tribunal correctly determined that Masimo’s patent claims survive invalidity scrutiny.

The case spanned 581 days—approximately 19 months—which is consistent with the typical Federal Circuit appellate timeline for patent validity appeals involving technical claim construction and evidentiary records from USPTO proceedings. The matter was resolved by affirmance with the appeal ultimately dismissed, meaning Apple exhausted its appellate avenue for invalidating this particular patent. No remand for further proceedings was ordered, delivering a clean and final outcome in Masimo’s favor that forecloses re-litigation of the same validity grounds at this appellate tier.

The Verdict & Legal Analysis

Outcome

The Court of Appeals for the Federal Circuit ordered and adjudged AFFIRMED on January 12, 2024, upholding the patentability determination in favor of Masimo Corporation. No damages were awarded at this appellate stage, as the proceeding concerned patent validity rather than infringement liability or monetary relief. Apple’s appeal was dismissed, leaving U.S. Patent No. 10,433,776 B2 fully enforceable and its claims intact against any future infringement actions.

Verdict Cause Analysis

The Federal Circuit’s affirmance turned on a patentability determination—specifically the court’s evaluation of Apple’s invalidity and cancellation arguments against Masimo’s asserted claims.

• The Federal Circuit upheld the prior tribunal’s finding that Masimo’s claimed low power pulse oximetry technology meets the statutory requirements of patentability, rejecting Apple’s invalidity arguments.
• Apple’s cancellation action—likely pursued through USPTO inter partes review proceedings—failed to produce sufficient prior art or claim construction arguments to overcome the presumption of patent validity.
• The affirmance signals that Masimo’s claim language covering low power physiological monitoring was found sufficiently novel and non-obvious over the cited prior art Apple presented during the challenge.
• The dismissal of Apple’s appeal on the basis of termination indicates that no triable issues of fact or reversible legal errors were identified by the Federal Circuit in the lower tribunal’s patentability analysis.

Legal Significance

1. 1. The Federal Circuit’s affirmance strengthens the presumption of validity for Masimo’s US10433776B2, making future invalidity challenges on the same grounds substantially harder to mount under 35 U.S.C. § 282.
2. 2. This outcome signals that low power optimization claims in wearable biosensor patents can survive rigorous appellate invalidity scrutiny, providing a meaningful precedent for patent prosecutors drafting similar claims in the physiological monitoring space.
3. 3. Pending district court litigation between Apple and Masimo involving Apple Watch blood oxygen features may be materially affected, as the enforceability of this validated patent could directly support Masimo’s infringement damages claims in parallel proceedings.

Strategic Takeaways

For Patent Attorneys:

• When drafting IPR or invalidity challenges against wearable biosensor patents, ensure prior art combinations specifically address low-power circuit architecture and sensor management claims—broad obviousness arguments failed Apple here.
• The Federal Circuit’s clean affirmance without remand underscores the importance of building a complete evidentiary record at the PTAB level; gaps in the administrative record cannot be supplemented on appeal.
• Practitioners representing challengers should evaluate whether inter partes reexamination or post-grant review on newly identified prior art grounds remains available, since the appeal dismissal forecloses only the grounds already litigated.
• Consider filing continuation claims in client portfolios that mirror the structural claim limitations upheld in US10433776B2, as the Federal Circuit has now validated that claim architecture in the low power physiological monitoring context.

For IP Professionals:

• In-house teams at wearable technology companies should immediately map their product sensor architectures against Masimo’s now-affirmed US10433776B2 claims to assess infringement exposure, particularly in devices featuring continuous SpO2 monitoring.
• Portfolio managers should treat this Federal Circuit affirmance as a trigger to audit licensing options with Masimo and evaluate whether cross-licensing negotiations in the broader Apple-Masimo dispute landscape could reduce litigation risk across the wearable health IP ecosystem.

For R&D Teams:

• Engineering teams developing low power pulse oximeters or SpO2-enabled wearables must treat US10433776B2 as a high-priority FTO obstacle; design-around strategies should focus on alternative power management architectures that fall outside the affirmed claim scope.
• R&D leaders should invest in documenting prior art and inventor notebooks for any proprietary low power biosensing innovations to establish independent development records, which can serve as both defensive evidence and the basis for competing patent filings.