Early last year, Apple made the bold decision to remove the blood-oxygen sensor from the Apple Watch Series 9 and Ultra 2 in the U.S. over a patent dispute with medical technology company Masimo. Since then, all new watches (including the Series 10, which launched several months later) have shipped with the sensor turned off, eliminating a feature available since the Series 6.
Now, Apple is turning the sensor back on for Apple Watch Series 9, Series 10, and Ultra 2 users. In a press release titled, “An update on Blood Oxygen for Apple Watch in the U.S.,” Apple says, “Users with these models in the U.S. who currently do not have the Blood Oxygen feature will have access to the redesigned Blood Oxygen feature by updating their paired iPhone to iOS 18.6.1 and their Apple Watch to watchOS 11.6.1.”
Apple says the update was enabled by a recent U.S. Customs ruling.
The new feature will now measure and calculate sensor data on the paired iPhone, and results can be viewed in the Respiratory section of the Health app. Previously, users could take a blood oxygen measurement at any time with the Blood Oxygen app as well as track occasional background measurements. It’s not clear whether this update will take away the ability to take instant readings on the watch.
Older watches that still have the blood-oxygen feature turned on will not be affected by the update, Apple says.
