Apple Watch Blood-Oxygen Patent Case: ITC Reopens, $634M Fine

The ITC has reopened its investigation into Apple's alleged infringement of Masimo's blood-oxygen sensor patents, while a separate ruling already ordered Apple to pay $634 million in damages. This is one of the biggest wearable tech legal battles in years, and it directly involves the SpO2 sensor sitting on the wrist of millions of Apple Watch Ultra 2 and Series 9 owners.

Masimo is a medical-grade pulse oximetry company. Their SpO2 tech is not hobby-grade. It powers hospital equipment, and they argue Apple lifted core sensor and algorithm concepts to build the blood-oxygen feature that debuted on Apple Watch Series 6 back in 2020. That feature has since become a selling point stacked against Garmin's Pulse Ox, Whoop's SpO2 monitoring, and Polar's nightly oxygen tracking.

The practical fallout for athletes matters here. Apple already pulled blood-oxygen functionality from new Watch sales in the US market for a stretch in early 2024 to sidestep an import ban. If the ITC pushes harder this time, we could see that restriction return or expand. For triathletes and altitude-focused trail runners who rely on SpO2 data for training load context, losing that metric on Apple Watch would push more users toward Garmin Fenix 8 or Coros Vertix 2S, both of which have no patent exposure on this feature.

The $634 million figure is large but Apple can absorb it. The bigger risk is a sustained import restriction that forces a hardware redesign. Masimo has already launched its own consumer wearable, the W1 and Freedom watch, so this is a competitor protecting IP and trying to carve out market space at the same time.

Verdict: This case is not resolved. Athletes invested in the Apple Watch ecosystem should watch the ITC ruling timeline closely. If SpO2 gets stripped again, Garmin and Coros are the obvious alternatives with mature, legally clean implementations.