Protracted litigation in the United StatesApple Watch blood oxygen patent warFinally, a crucial turning point arrived. According toLatest Reuters News reportThis week, a judge at the U.S. International Trade Commission (ITC) issued a preliminary ruling finding that Apple's current "alternative" Apple Watch blood oxygen detection solution used in the U.S. market does not infringe on patents held by medical device manufacturer Masimo.
This ruling means that Apple has successfully defended its legal position and temporarily avoided a new wave of product import and sales bans; however, this preliminary decision still needs final approval and confirmation from all members of the U.S. International Trade Commission.
Depriving smartwatches of computing power: handing over core computing to the iPhone
At the heart of this controversy lies a cleverly devised technical circumvention strategy proposed by Apple in August 2025 to bypass the import ban.
Prior to this, Masimo sued Apple Watch for infringing its optical sensing and data processing patents on the built-in blood oxygen saturation measurement function, leading to a temporary sales ban on Apple Watches with this feature in the United States. To relist the watch and restore the functionality, Apple completely overhauled the underlying operating mechanism of blood oxygen detection:
• The sensor is downgraded to a "pure data collection device":The Apple Watch sold in the United States today uses an optical sensor that only collects "raw optical data" of microvascular reflections; the watch's chip does not perform any calculations or analysis of blood oxygen levels.
• Transferring computing power to mobile phones:This massive amount of raw, unprocessed data is transmitted instantly to the paired iPhone. The iPhone's powerful internal processor then performs the core calculations for the blood oxygenation algorithm.
• Terminal display limitations:The final blood oxygen saturation test results can only be viewed on the iPhone screen; the Apple Watch screen will no longer display the value directly.
This alternative solution, which "reduces the watch's computing power and hands it over to the phone," has previously successfully persuaded U.S. Customs and Border Protection (CBP) to grant it compliance clearance, allowing Apple Watches in the United States to substantially restore their blood oxygen measurement function.
Masimo's Counterattack and the Final Battle of ITC
Masimo was clearly very dissatisfied with the release of the goods by U.S. Customs.
The company not only directly sued U.S. Customs and Border Protection (CBP), accusing it of overstepping its authority and operating illegally, but also pressured the U.S. International Trade Commission (ITC) to thoroughly investigate whether Apple's new plan violated the initial import ban. However, the ITC's preliminary ruling by an administrative law judge effectively refuted Masimo's claims, proving that Apple's strategy of physically separating "data collection" and "data processing" has withstood the test in terms of technical compliance and patent definition.
