When Apple announced thereturn of the Apple Wach Blood Oxygen feature in the U.S., many figured Masimo would fight back. It just did.

A federal jury in California ruled Friday that Apple must pay medical device maker Masimo $634 million for infringing a patent on blood oxygen monitoring technology.

A federal jury in California said on Friday that Apple owes medical-monitoring technology company Masimo $634 million for infringing a patent covering blood-oxygen reading technology.

Apple just scored an important win in its ongoing battle with Masimo over patents related to the Apple Watch’s blood oxygen feature. Here are the details. more…

Apple’s requests to overturn a $634 million patent verdict and secure a new trial in its long-running legal battle with Masimo were denied. Here are the details.

A few days ago, Masimo sued U.S. Customs over its decision to let Apple resume selling the Apple Watch in the United States with the blood oxygen feature enabled. Now, the government agency has responded with a motion to dismiss the lawsuit. Here are the details. more…

A federal jury in California has sided with Masimo in a patent battle with Apple over Apple Watch’s blood oxygen feature. The jury awarded Masimo $634 million in damages and concluded that Apple infringed on a Masimo patent covering low power pulse oximeter features. As explained by Daily Journal, much of the case centered on whether Apple Watch can be categorized as a “patient monitor” per Masimo’s patent. more…

Masimo is suing US Customs this time.

Medical monitoring technology company Masimo sued U.S. Customs and Border Protection on Wednesday over a decision by the agency that allowed Apple to import Apple Watches with blood-oxygen reading technology during a patent dispute between the companies.

There are two new developments in Apple’s ongoing legal battle with health technology company Masimo over the Apple Watch’s blood oxygen feature. First, an ITC Administrative Law Judge Monica Bhattacharyya found in an initial determination that Apple’s redesigned version of the Apple Watch’s blood oxygen feature does not infringe Masimo’s patents. Second, the Federal Circuit has affirmed the ITC’s initial exclusion order, meaning the original version of the blood oxygen feature on Apple Watch is still banned in the United States. more…

Apple and US Customs and Border Protection allegedly violated the law by finding a loophole in an International Trade Commission ruling that bypassed an Apple Watch sales ban -- all without Masimo.

Medical technology company Masimo on Wednesday filed a lawsuit against U.S. Customs and Border Protection in which it challenged the agency's decision to allow Apple to restore blood oxygen monitoring to its Apple Watch models (via Bloomberg Law). In a complaint filed Wednesday in the US District Court for the District of Columbia, Masimo said that Customs acted unlawfully when it ruled on August 1 that Apple can import watches with pulse oximetry technology – a reversal of the agency's decision from last year – without notifying Masimo. Masimo said it only discovered the ruling on August 14, when Apple publicly announced it would be reintroducing the pulse oximetry functionality through a software update. The medical device maker claims Customs and Border Protection exceeded its authority when it issued the ruling permitting Apple's redesigned approach. Apple's workaround offloads blood oxygen calculations from the Apple Watch to a paired iPhone, where it performs similar functionality to what the ITC originally judged to have infringed Masimo's patents. Masimo is seeking a temporary restraining order and preliminary injunction to block the Customs decision. "CBP's function is to enforce ITC exclusion orders, not to create loopholes that render them ineffective," Masimo said. The dispute originates from an International Trade Commission ruling in December 2023 that found Apple's blood oxygen sensors infringed Masimo's patents, leading to an import ban on Apple Watch Series 9 and Ultra 2 models that have the feature enabled. Apple paused sales in the U.S. for several days before resuming them on January 18, 2024. The Series 9 and Ultra 2 models then went back on the market without blood oxygen monitoring, up until Apple's release of iOS 18.6.1 and watchOS 11.6.1 last week, which shifted the feature's calculations to paired iPhones.Tag: Masimo This article, "Apple Blood Oxygen Feature Workaround Sparks Fresh Masimo Lawsuit" first appeared on MacRumors.com Discuss this article in our forums

Today, Apple appeared before the U.S. Court of Appeals for the Federal Circuit in an effort to overturn a ruling that blocked U.S. sales of Apple Watches with blood-oxygen sensors back in late 2023. Here’s how it went. more…

Apple asked a U.S. appeals court on Monday to overturn a trade tribunal's decision which forced it to remove blood-oxygen reading technology from its Apple Watches, in order to avoid a ban on its U.S. smartwatch imports.

Apple and Masimo have been battling it out in court for years.

The accuracy of the tested medical-grade pulse oximeter changed year-to-year at a large hospital compared to concurrent arterial blood gas saturation, potentially complicating safe clinical decision-making and application of evidence-based medicine. Errors of false hypoxemia became more common, thre …

Apple's current blood oxygen sensing implementation in the U.S. does not infringe on patents owned by Masimo and Apple will not face a revived import ban, a U.S. International Trade Commission judge said this week (via Reuters). After Apple was found to have violated Masimo's patents related to blood oxygen sensing, the Apple Watch faced a U.S. import ban that caused Apple to briefly pause sales of the device in December 2023 before Apple earned a temporary stay. Apple disabled blood oxygen sensing in January 2024, and was able to resume selling the Apple Watch without the functionality. In August 2025, Apple found a workaround and was able to bring blood oxygen sensing back to U.S. Apple Watch owners. Data is collected by the blood oxygen sensor on the Apple Watch, but it is processed on a paired iPhone rather than the watch itself, and the resulting information can only be viewed on the iPhone. Apple said the updated process did not violate the ITC ban, or infringe on Masimo's patents, and it was cleared by U.S. Customs and Border Protection (CBP). Masimo did not agree with the decision and it quickly filed a lawsuit against CBP, accusing the agency of acting unlawfully and exceeding its authority. Masimo also pushed the ITC to look into whether Apple's solution violated the original import ban. The ITC ended up siding with Apple, and said that Apple's workaround does not violate Masimo patents. Since today's decision is preliminary, the full commission will need to affirm the ruling. Though Apple scored a win with the ITC, Masimo came out ahead in a separate appeals ruling today. The U.S. Court of Appeals for the Federal Circuit affirmed the original 2023 ITC decision that led to the Apple Watch import ban. The appeals court said that the Apple Watch did indeed infringe on Masimo's patents, and it declined to overturn the ban. Apple said that it would continue to investigate "all avenues for further review" in light of the appeals court decision. In November 2025, Apple also lost the patent infringement lawsuit that Masimo filed against it. A federal jury awarded Masimo $634 million, which Apple is appealing.Related Roundup: Apple Watch 11Tags: Apple Lawsuits, Masimo, Patent LawsuitsBuyer's Guide: Apple Watch (Neutral) This article, "ITC Judge Rules Apple Watch Blood Oxygen Workaround Does Not Infringe Masimo Patents" first appeared on MacRumors.com Discuss this article in our forums

The U.S. ITC has denied a request by Masimo to reinstate a ban on the Apple Watch, closing its case on alleged blood oxygen patent infringement.

A US appeals court has found in favor of Masimo in its fight against Apple over pulse oximetry patents, but in the court that matters, a ruling makes it clear that there won't be another ban on the Apple Watch.

Plus: Masimo sues the US Customs and Border Protection over the Apple Watch's blood oxygen sensor, Insta360 has a new action camera, and BikeOn's power meter is tiny and affordable.

Last week, when Apple announced the release of a “redesigned Blood Oxygen feature” to the Apple Watch, many figured Masimo (who had been suing Apple over patents related to the feature), would look for a way to fight back. Today, the company did just that and filed a new lawsuit. But this time, it’s against the US Customs and Border Protection. Here’s why. more…