Overview

• Apple released iOS 18.6.1 and watchOS 11.6.1 on August 14 to reintroduce a redesigned Blood Oxygen feature for U.S. Apple Watch Series 9, Series 10 and Ultra 2 models.
• The updated watches still collect raw sensor data but rely on the paired iPhone to process readings and present results in the Respiratory section of the Health app.
• Manual and background blood-oxygen measurements return to devices that lost the feature after an ITC ruling in late 2023 led Apple to disable it on new U.S. Watch shipments.
• Apple credits a recent U.S. Customs decision for permitting importation of watches with the software workaround, though the ruling’s text remains unpublished.
• The broader patent dispute with Masimo continues, with Apple’s appeal pending at the Federal Circuit and key patents set to expire in 2028.