Apple has reintroduced blood oxygen monitoring to the Apple Watch but with a twist. A new software update rolling out today enables a redesigned version of the feature for the Apple Watch Series 9, 10, and Ultra 2. This update bypasses the US International Trade Commission (ITC) import ban by shifting the measurement process to the iPhone paired with the watch.
How the New Blood Oxygen Feature Works
With the update, blood oxygen data will no longer be processed on the Apple Watch itself. Instead, it will be measured and calculated on the paired iPhone. While users won’t be able to see the readings directly on their watch, they can still access the results in the Health app on their iPhone under the Respiratory section.
This redesign only applies to Apple Watches sold in the US after January 17, 2024 — the date when the ITC ban took full effect. Watches sold before this date or outside the US will retain the original on-device monitoring feature.
To check if your watch is affected, look for a serial number ending with LW/A. Eligible users must update to watchOS 11.6.1 and iOS 18.6.1 to access the redesigned feature.
The Legal Battle Behind the Change
The update is Apple’s workaround for an ongoing legal dispute with Masimo, a medical device company known for its pulse oximeters. Masimo accused Apple of patent infringement and theft of trade secrets, filing a lawsuit in 2020. In 2021, Masimo took the case to the ITC, which resulted in an import ban on certain Apple Watch models in December 2023.
Apple, in turn, has filed its own lawsuits against Masimo, claiming its smartwatches are Apple Watch clones. The company also submitted a 916-page appeal to overturn the ban, which is still under review. Masimo’s patents involved in the case are set to expire in 2028.
