Apple Blood Oxygen Feature Workaround Sparks Fresh Masimo Lawsuit - MacRumors
Skip to Content

Apple Blood Oxygen Feature Workaround Sparks Fresh Masimo Lawsuit

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).

apple watch series 6 blood oxygen monitoring 1
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

Popular Stories

Apple Event Logo

Apple's Next Era Begins September 1

Thursday May 7, 2026 10:36 am PDT by
Apple recently announced that Tim Cook will be stepping down as CEO later this year, after 15 years of leading the company. Effective September 1, Apple's hardware engineering chief John Ternus will become the company's next CEO, while Cook will become executive chairman of Apple's board of directors. In his new role, Apple said Cook will assist with "certain aspects" of the company,...
General Apps Reddit Feature

Reddit Starts Blocking Mobile Website, Pushing Users to App Instead

Monday May 11, 2026 6:10 am PDT by
Social network Reddit recently began blocking mobile visitors to its website while pushing them to download the official Reddit app, and it's fair to say that the move is not going down well with users. If you visit reddit.com on your iPhone today, you may see a new popup that can't be dismissed, asking you to "get the app to keep using Reddit." A Reddit spokesperson told Ars Technica...
Four iPhone 18 Pro Colors Mock Feature

iPhone 18 Pro Launching in September With These 10 New Features

Saturday May 9, 2026 6:03 am PDT by
While the iPhone 18 Pro and iPhone 18 Pro Max are not launching until September, there are already plenty of rumors about the devices. It was initially reported that the iPhone 18 Pro models would have fully under-screen Face ID, with only a front camera visible in the top-left corner of the screen. However, the latest rumors indicate that only one Face ID component will be moved under the...

Top Rated Comments

McWetty Avatar
10 months ago
Once again, the only people that benefit from protracted lawsuits are the lawyers…
Score: 41 Votes (Like | Disagree)
contacos Avatar
10 months ago

Masimo is putting people’s lives at risk. These health monitoring systems put on to a consumer product like an Apple Watch saves lives. OK.
So ...? Apple could license it from them in that case
Score: 31 Votes (Like | Disagree)
Pitogyro Avatar
10 months ago

Masimo needs to get a life.
So someone steals your life's work and your advice to them is to get a life. OK.
Score: 31 Votes (Like | Disagree)
Pitogyro Avatar
10 months ago

Masimo is putting people’s lives at risk. These health monitoring systems put on to a consumer product like an Apple Watch saves lives. OK.
So because Masimo's technology saves lives, it should be stolen and monetized by someone else. OK.
Score: 30 Votes (Like | Disagree)
andyadler Avatar
10 months ago

Masimo is putting people’s lives at risk. These health monitoring systems put on to a consumer product like an Apple Watch saves lives. OK.
If someone is so concerned about monitoring their blood oxygen level, a pulse oximeter is an inexpensive, easy to carry around accessory tool. Nobody’s life is at risk because their Apple Watch lacks that feature.
Score: 29 Votes (Like | Disagree)
surferfb Avatar
10 months ago

Then maybe Apple should just pay to use it like every other company has to do who wants to use Masimo's technology.


Aah, yes, Masimo, the famous patent troll. We shouldn't lend to much credit to the hundreds upon hundreds of products they have when that runs the risk of infringing on our dear Apple, I guess.
While I wouldn’t call Masimo a patent troll, they’ve reportedly asked for an absurd amount of money (like more than doubling their annual revenue absurd) and refused to negotiate on that number for a patent that many observers argue never should have been granted in the first place, given that pulse oximetry technology already existed long before Masimo’s patent.

That said, if what Masimo claims about the process is true (I.e. CBP is blatantly overstepping its authority) they should sue to get it overturned and I hope they win. We absolutely don’t want government breaking the law to do favors for the President’s “friends”/allies. But this is the first I’ve heard anyone mention that it might be the case, and think someone somewhere would have mentioned that before now (maybe they did and I missed it though).
Score: 21 Votes (Like | Disagree)