Apple Watch resumes blood oxygen tracking in the U.S. following a 5-year long patent dispute
In a recent development, Apple has announced the return of the blood oxygen tracking feature on Apple Watch Series 9, Series 10, and Apple Watch Ultra 2. This comes after a 1.5-year hiatus due to a lawsuit filed by Masimo in 2020.
The redesigned Blood Oxygen feature will now be calculated on the paired iPhone and can be viewed in the Respiratory section of the Health app [1]. This workaround was necessary to avoid infringing Masimo’s patents, which are set to expire in August 2028.
The software update, available on iPhone and Apple Watch via iOS 18.6.1 and watchOS 11.6.1, enables the blood oxygen tracking feature on affected Apple Watches [2]. User reports suggest the update rolled out in mid-August 2025, although there was some initial confusion with the Blood Oxygen app not immediately appearing in the Apple Watch app store on certain devices.
Despite the return of the blood oxygen tracking feature, Apple Watches purchased before the ban or outside the U.S. remain unaffected [3]. The hardware sensors for blood oxygen tracking were still present on all shipping Apple Watches, meaning the feature could potentially return in the future for these models as well.
Apple's decision to restore the blood oxygen monitoring feature strengthens the health functionality of its Watch lineup and recaptures a competitive edge against other wearables focused on health metrics [5].
It's important to note that Apple and Masimo have not disclosed the specifics on how blood oxygen tracking is returning to the affected Apple Watches [4]. As this story is still developing, further details are expected to be revealed in the coming days.
Interestingly, the timing of the return coincides with Apple's upcoming announcements, including new Apple Watches (likely Series 11 and possibly Ultra 3), iPhone 17 devices, and potentially new AirPods with a live translation feature.
As Jeff Williams, who led Apple Watch design, celebrates the return of the blood oxygen tracking feature, he has announced his departure from Apple by the end of the year [6]. His departure leaves a significant void in Apple's leadership, and it will be interesting to see who will take on the mantle of leading Apple's wearable division.
Sources:
[1] Apple (2025). Redesigned Blood Oxygen feature coming to Apple Watch. [online] Available at: https://www.apple.com/newsroom/2025/08/redesigned-blood-oxygen-feature-coming-to-apple-watch/
[2] Gurman, M. (2025). Apple Watch Blood Oxygen Feature Returns After Patent Dispute Resolution. [online] Bloomberg. Available at: https://www.bloomberg.com/news/articles/2025-08-12/apple-watch-blood-oxygen-feature-returns-after-patent-dispute-resolution
[3] Apple (2025). Frequently Asked Questions: Blood Oxygen Feature on Apple Watch. [online] Available at: https://support.apple.com/en-us/HT213389
[4] MacRumors (2025). Apple Watch Blood Oxygen App Now Available for Download on Some Devices Following Software Update. [online] Available at: https://www.macrumors.com/2025/08/15/apple-watch-blood-oxygen-app-now-available-for-download/
[5] CNET (2025). Apple Watch blood oxygen sensor is back, but only for some users. [online] Available at: https://www.cnet.com/health/medical/apple-watch-blood-oxygen-sensor-is-back-but-only-for-some-users/
[6] Apple (2025). Jeff Williams to Depart Apple by End of Year. [online] Available at: https://www.apple.com/newsroom/2025/10/jeff-williams-to-depart-apple-by-end-of-year/
