Apple Watch Infringed Masimo's Pulse Oximetry Patent, US Judge Rules

Apple infringed on one of medical technology company Masimo's pulse oximeter patents when it launched Apple Watch models that use light sensors to measure the amount of oxygen in the blood, an International Trade Commission (ITC) judge ruled on Tuesday.

apple watch 6s 202009
Masimo, which designs pulse oximetry devices, has been embroiled in an ongoing battle with Apple over several health capabilities found in some Apple Watch models, and Masimo has been pushing to have the models banned in the United States.

Medical grade pulse oximetry devices are what Masimo specializes in, and pulse oximetry is a feature that Apple added to the Apple Watch with the Series 6 model. The feature found in the Series 6 and later Apple Watch models uses light to detect the amount of oxygen in the blood, with the feature joining heart rate monitoring and ECG capabilities.

In June 2021, Masimo filed a patent infringement lawsuit with the ITC asking it to halt imports of the Apple Watch Series 6 because of patent infringements related to blood oxygen monitoring.

In Tuesday's ruling, the judge concluded that four other patents at issue were not infringed. The ITC will now consider whether to implement an import ban on Apple Watch models that include the blood oxygen monitoring feature, according to the medical device maker. The final determination is expected to be completed by May 10.

"We are happy that the judge recognized Apple's infringement of Masimo's pulse oximetry technology and took this critical first step toward accountability," said Masimo CEO Joe Kiani in a statement given to MD+DI. "Today's decision should help restore fairness in the market. Apple has similarly infringed on other companies' technologies, and we believe today's ruling exposes Apple as a company that takes other companies' innovations and repackages them."

"We respectfully disagree with today's decision, and look forward to a full review by the Commission," Apple said in a statement reported by Reuters.

Masimo initially sued Apple in January 2020, accusing the company of stealing trade secrets and improperly using Masimo inventions. In the prior filing, Masimo claimed that Apple sneakily poached Masimo employees and used patented Masimo technology when developing the sensors used in the Apple Watch.

Popular Stories

Apple Announces Special Event in New York Feature

Apple Announces Special Event in New York, London, and Shanghai on March 4

Monday February 16, 2026 6:05 am PST by
Apple today announced a "special Apple Experience" in New York, London, and Shanghai, taking place on March 4, 2026 at 9:00am ET. Apple invited select members of the media to the event in three major cities around the world. It is simply described as a "special Apple Experience," and there is no further information about what it may entail. The invitation features a 3D Apple logo design...
M3 iPad Air

Apple's Next Two Products Are Coming Soon

Thursday February 12, 2026 11:17 am PST by
Apple plans to release an iPhone 17e and an iPad Air with an M4 chip "in the coming weeks," according to the latest word from Bloomberg's Mark Gurman. "Apple retail employees say that inventory of the iPhone 16e has basically dried out and the iPad Air is seeing shortages as well," said Gurman. "I've been expecting new versions of both (iPhone 17e and M4 iPad Air) in the coming weeks."...
Apple Sales Coach App

Apple Launching New 'Sales Coach' App

Friday February 13, 2026 2:01 pm PST by
Apple plans to launch a rebranded "Sales Coach" app on the iPhone and iPad later this month, according to a source familiar with the matter. "Sales Coach" will arrive as an update to Apple's existing "SEED" app, and it will continue to provide sales tips and training resources to Apple Store and Apple Authorized Reseller employees around the world. For example, there are articles and videos...
Coffee Burgundy and Purple iPhone 18 Pro Mock

Five iPhone 18 Pro Features Revealed in New Report

Friday February 13, 2026 8:43 am PST by
While the iPhone 18 Pro and iPhone 18 Pro Max are still seven months away, an analyst has revealed five new features the devices will allegedly have. Rumored color options for the iPhone 18 Pro models In a research note with investment firm GF Securities on Thursday, analyst Jeff Pu outlined the following upgrades for the iPhone 18 Pro models: Smaller Dynamic Island: It has been rumored...
iOS 26 Home Feature

Three New Apple Home Products Rumored for 2026

Friday February 13, 2026 4:18 pm PST by
Apple has a long list of new products rumored for 2026, including a series of home products that will see the company establishing more of a presence in the smart home space. Robots are on the horizon for 2027, but the 2026 releases will be a little tamer. HomePod mini We're expecting a new HomePod mini 2 to launch at any time. Apple isn't going to update the device's design, but we could...

Top Rated Comments

kesenwangs Avatar
41 months ago

Making numbers up but truly seems 99% here will blindly defend their Daddy Apple. The mods here don’t seem to do anything about it at all.
Why should mods police general opinions? If a majority wants to think or express themselves in a similar manner that’s their choice. It’s not really a role of mod’s to police conversations that don’t go against any of the sites policies.
Score: 34 Votes (Like | Disagree)
41 months ago
Before people rush here accusing them of patent trolling, just think whether apple would do the same if the other company infringed apples patents.
Score: 23 Votes (Like | Disagree)
Skeptical.me Avatar
41 months ago
If Apple truly infringed on the patent of the technology, they should be held accountable
Score: 23 Votes (Like | Disagree)
pdaholic Avatar
41 months ago
https://www.macrumors.com/2021/06/30/masimo-apple-watch-series-6-itc-import-ban/

Fun to look back at this thread for all the comments saying Masimo is wasting their time trying to sue Apple.
Score: 21 Votes (Like | Disagree)
laptech Avatar
41 months ago
Apple has a history of this, hiring/headhunting/poaching employees from rival companies and then low and behold, patents that Apple were not approved to use turn up in their products. Didn't this happen with with Qualcomm and Broadcom back in the day when they poached employees from those companies and didn't an ex-employee of a car company get arrested for stealing company files when poached by Apple for their Apple car project?
Score: 18 Votes (Like | Disagree)
WiiDSmoker Avatar
41 months ago

https://www.macrumors.com/2021/06/30/masimo-apple-watch-series-6-itc-import-ban/

Fun to look back at this thread for all the comments saying Masimo is wasting their time trying to sue Apple.
Making numbers up but truly seems 99% here will blindly defend their Daddy Apple. The mods here don’t seem to do anything about it at all.
Score: 15 Votes (Like | Disagree)