Apple changed Apple Watch Blood Oxygen twice in the United States. The first redesign, sold from January 18, 2024, left the optical hardware in affected Series 9 and Ultra 2 watches but disabled the feature. A later redesign moved the measurement calculation to the paired iPhone. Apple enabled that version for eligible U.S. Series 9, Series 10 and Ultra 2 units with iOS 18.6.1 and watchOS 11.6.1 in August 2025.
This did not erase the International Trade Commission (ITC) exclusion order. Instead, Apple sought products that U.S. Customs and Border Protection (CBP) determined were outside the order’s scope. The underlying patent dispute and review of the later redesign continued into 2026.
What the ITC order actually did
Masimo and Cercacor alleged that Apple Watches infringed patents covering wearable pulse-oximetry technology. The ITC found infringement of two Masimo patents and issued an exclusion order affecting covered Apple Watches with the disputed Blood Oxygen implementation. The Federal Circuit later affirmed that original ITC decision in Apple Inc. v. International Trade Commission, No. 24-1285 (Federal Circuit opinion).
An exclusion order is primarily an import remedy. It directs Customs to stop covered products from entering the United States; it is not the same as a federal court injunction that directly orders every retailer to stop selling inventory. Apple nevertheless paused U.S. online sales of affected models while the order approached and while the courts considered temporary stays.
#1 Best Overall
![Apple Watch Series 11 [GPS 46mm] Smartwatch with Jet Black Aluminum Case with Black Sport Band - M/L. Sleep Score, Fitness Tracker, Health Monitoring, Always-On Display, Water Resistant](https://m.media-amazon.com/images/I/416RQ0rtsUL._SL160_.jpg)
- A FULL-FEATURED HEALTH TRACKER—Apple Watch Series 11 gives you invaluable insights about your body, right from your wrist. Take an ECG anytime* and get alerts for a high and low heart rate or an irregular rhythm*—so you can stay closer to your heart. You can also view your overnight health tracking metrics with the Vitals app* and be notified of possible sleep apnea.*
- KNOW YOUR SLEEP SCORE—With advanced sleep tracking, Series 11 gives you a daily sleep score. It’s an easy way to help measure and understand the quality of your sleep, so you can make it more restorative.
- GET HYPERTENSION NOTIFICATIONS—Did you know that Series 11 can spot signs of chronic high blood pressure? By analyzing how your blood vessels respond to beats of the heart, it can notify you of possible hypertension.*
- SAFETY FEATURES—A smartwatch that puts your safety first. Series 11 can detect a hard fall or severe car crash, automatically help connect you with emergency services, and notify your emergency contacts.* Check In can automatically notify a loved one when you’ve arrived at your destination.
- A POWERFUL FITNESS TRACKER—With advanced metrics and motivating features like Pacer, Heart Rate Zones, training load, and Workout Buddy powered by Apple Intelligence from your nearby iPhone*—Series 11 is made to help everyone stay active, from runners and hikers to strength-training enthusiasts.
The order did not cover every Apple Watch. The initial practical impact centered on the Apple Watch Series 9 and Apple Watch Ultra 2 sold for the U.S. market.
Timeline: from the original watches to the iPhone-based redesign
| Date | What happened |
|---|---|
| September 2023 | Apple introduced Apple Watch Series 9 and Apple Watch Ultra 2 with Blood Oxygen capability. |
| October 2023 | The ITC issued its infringement decision and exclusion order. |
| December 21, 2023 | Apple began pausing U.S. online sales of affected models ahead of the order taking effect. |
| December 26, 2023 | The exclusion order became effective, subject to later court action. |
| January 12, 2024 | CBP determined that Apple’s proposed redesign, which disabled Blood Oxygen, fell outside the order’s scope. |
| January 18, 2024 | Apple resumed U.S. sales of Series 9 and Ultra 2 versions without functional Blood Oxygen readings after the Federal Circuit declined to continue a stay. |
| January 7, 2025 | CBP issued ruling H338254 on a later redesign, identified as “Redesign 2.” |
| August 1, 2025 | CBP issued another ruling concerning the later redesigned watch. |
| August 14, 2025 | Apple announced that eligible U.S. watches could regain the redesigned feature through iOS 18.6.1 and watchOS 11.6.1. |
| November 14, 2025 | The ITC instituted a combined modification and enforcement proceeding concerning the later redesign. |
| January 28, 2026 | An evidentiary hearing was held in that proceeding. |
| March 19, 2026 | The Federal Circuit affirmed the original ITC decision. Separately, an administrative-law judge found the later implementation non-infringing in the redesign proceeding, subject to the remaining review process. |
The CBP rulings are H338254 and H351038. Apple described the later ITC proceeding in its SEC filing.
The January 2024 workaround disabled the feature, not necessarily the sensor
Apple’s first U.S. workaround was a software and functionality change. The affected watches retained relevant optical sensing hardware, but users could not obtain a Blood Oxygen reading.
Rank #2
![Apple Watch Series 11 [GPS 42mm] Smartwatch with Rose Gold Aluminum Case with Light Blush Sport Band - S/M. Sleep Score, Fitness Tracker, Health Monitoring, Always-On Display, Water Resistant](https://m.media-amazon.com/images/I/31caPPnRysL._SL160_.jpg)
- A FULL-FEATURED HEALTH TRACKER—Apple Watch Series 11 gives you invaluable insights about your body, right from your wrist. Take an ECG anytime* and get alerts for a high and low heart rate or an irregular rhythm*—so you can stay closer to your heart. You can also view your overnight health tracking metrics with the Vitals app* and be notified of possible sleep apnea.*
- KNOW YOUR SLEEP SCORE—With advanced sleep tracking, Series 11 gives you a daily sleep score. It’s an easy way to help measure and understand the quality of your sleep, so you can make it more restorative.
- GET HYPERTENSION NOTIFICATIONS—Did you know that Series 11 can spot signs of chronic high blood pressure? By analyzing how your blood vessels respond to beats of the heart, it can notify you of possible hypertension.*
- SAFETY FEATURES—A smartwatch that puts your safety first. Series 11 can detect a hard fall or severe car crash, automatically help connect you with emergency services, and notify your emergency contacts.* Check In can automatically notify a loved one when you’ve arrived at your destination.
- A POWERFUL FITNESS TRACKER—With advanced metrics and motivating features like Pacer, Heart Rate Zones, training load, and Workout Buddy powered by Apple Intelligence from your nearby iPhone*—Series 11 is made to help everyone stay active, from runners and hikers to strength-training enthusiasts.
- The Blood Oxygen app or icon could still appear on the watch.
- Starting a reading produced a notice that the feature was unavailable.
- Other Apple Watch health and activity functions continued to operate.
- The limitation applied to particular U.S. units, not universally to every Series 9 or Ultra 2 worldwide.
That distinction matters. Saying Apple “removed the blood-oxygen sensor” overstates what the legal record establishes. The more accurate description is that Apple disabled the feature in the U.S. redesign accepted by CBP in January 2024. Later CBP materials discuss that earlier ruling and the subsequent design (H351038).
Do these 3 things before closing this tab:
1Clear out junk files and repair common Windows errors2Scan for outdated or missing drivers - takes under a minute3Repair Windows errors before they cause bigger problemsThe later redesign moved the calculation to the iPhone
Apple’s subsequent approach kept the watch as the data-collection device but shifted the final Blood Oxygen measurement and calculation to the paired iPhone:
- The watch records optical sensor signals.
- The paired iPhone performs the processing used to calculate the Blood Oxygen result.
- The result is displayed in the iPhone Health app under the Respiratory section.
CBP described the change as relocating processors responsible for the final calculation from the watch to the redesigned iPhone. In other words, the sensing hardware and the location of the legally significant processing are separate questions. Moving software processing can change how an import analysis applies, but it does not by itself prove that every patent issue is permanently resolved. See CBP H338254 and CBP H351038.
Rank #3
![Apple Watch SE 3 [GPS 40mm] Smartwatch with Starlight Aluminum Case with Starlight Sport Band - S/M. Fitness and Sleep Trackers, Heart Rate Monitor, Always-On Display, Water Resistant](https://m.media-amazon.com/images/I/31YiTby0pOL._SL160_.jpg)
- GET SMARTER HEALTH INSIGHTS—Apple Watch SE 3 is an advanced health tracker that helps you better understand your body. The smartwatch sends alerts for an irregular heart rhythm, or an unusually high or low heart rate.* You can view your overnight health tracking metrics with the Vitals app,* track your sleep score, and get sleep apnea notifications.*
- A GREAT FITNESS TRACKER—SE 3 can track your workouts in a healthy number of ways—from running and strength training to simply achieving your 10K steps a day. With real-time metrics and Workout Buddy powered by Apple Intelligence from your nearby iPhone,* you’ll hit your goals like never before.
- KEEP HELP CLOSE AT HAND—SE 3 is a smartwatch that can detect a hard fall or severe car crash and automatically help connect you to emergency services and notify your emergency contacts.* Check In can automatically notify a loved one when you’ve arrived at your destination.
- WOMEN’S HEALTH INSIGHTS—SE 3 has advanced sensors that track your wrist temperature while you sleep. With this smartwatch, you can log your periods and symptoms, get period predictions, and get notified of cycle deviations.*
- GREAT BATTERY LIFE AND FASTER CHARGING—Enjoy a smartwatch with all-day, 18-hour battery life* from sunup to sundown. Then charge up to twice as fast as SE 2* and get up to 8 hours of battery in just 15 minutes.*
How Blood Oxygen returned in the United States
On August 14, 2025, Apple said owners of certain U.S. watches that originally lacked Blood Oxygen could activate the redesigned feature by updating both devices:
- Update the paired iPhone to iOS 18.6.1.
- Update the Apple Watch to watchOS 11.6.1.
- Open the Blood Oxygen feature on the watch when prompted or as applicable.
- View completed measurements in the paired iPhone’s Health app, in Respiratory.
Apple’s announcement covers eligible U.S. versions of the Apple Watch Series 9, Series 10 and Apple Watch Ultra 2 that currently lacked the original feature. It does not say that every watch in those model families qualifies. Model configuration, region, purchase history and whether the watch already had Blood Oxygen matter. Apple also said the update did not affect units previously purchased with the original feature or watches purchased outside the United States. The primary announcement is available from Apple.
The Tool Desk
Outbyte PC Repair FREERepair Windows errors before they cause bigger problemsFix Now →Outbyte Driver Updater FREEFix the driver behind crashes, sound loss and screen glitchesFind Drivers →What owners should check
Identify the exact unit
Do not rely on “Series 9,” “Series 10” or “Ultra 2” alone. Check the country in which the watch was originally sold, its model or part number, purchase date and whether Blood Oxygen currently opens and completes a reading.
Rank #4
![Apple Watch SE 3 [GPS 40mm] Smartwatch with Midnight Aluminum Case with Midnight Sport Band - S/M. Fitness and Sleep Trackers, Heart Rate Monitor, Always-On Display, Water Resistant](https://m.media-amazon.com/images/I/31Gq8SToFJL._SL160_.jpg)
- GET SMARTER HEALTH INSIGHTS—Apple Watch SE 3 is an advanced health tracker that helps you better understand your body. The smartwatch sends alerts for an irregular heart rhythm, or an unusually high or low heart rate.* You can view your overnight health tracking metrics with the Vitals app,* track your sleep score, and get sleep apnea notifications.*
- A GREAT FITNESS TRACKER—SE 3 can track your workouts in a healthy number of ways—from running and strength training to simply achieving your 10K steps a day. With real-time metrics and Workout Buddy powered by Apple Intelligence from your nearby iPhone,* you’ll hit your goals like never before.
- KEEP HELP CLOSE AT HAND—SE 3 is a smartwatch that can detect a hard fall or severe car crash and automatically help connect you to emergency services and notify your emergency contacts.* Check In can automatically notify a loved one when you’ve arrived at your destination.
- WOMEN’S HEALTH INSIGHTS—SE 3 has advanced sensors that track your wrist temperature while you sleep. With this smartwatch, you can log your periods and symptoms, get period predictions, and get notified of cycle deviations.*
- GREAT BATTERY LIFE AND FASTER CHARGING—Enjoy a smartwatch with all-day, 18-hour battery life* from sunup to sundown. Then charge up to twice as fast as SE 2* and get up to 8 hours of battery in just 15 minutes.*
Confirm the iPhone requirement
The redesigned U.S. workflow depends on a compatible paired iPhone because the phone performs the calculation and stores the result in Health. This is different from expecting a complete result to be calculated and shown solely on the watch.
Be cautious with used and imported watches
- A listing that says “Blood Oxygen sensor” may describe hardware, not an enabled feature.
- An imported watch can have different regional functionality, cellular-band support, warranty terms or regulatory treatment.
- Ask the seller to demonstrate a completed reading and verify that Activation Lock has been removed.
- Check that both the watch and paired iPhone can receive the required software updates.
What the 2026 legal developments mean
Apple’s ability to sell a redesigned product did not end the dispute. The Federal Circuit’s March 19, 2026 opinion affirmed the original ITC decision involving the initial implementation. That is a separate question from whether a later design falls within the order or infringes the patents in the redesign proceeding.
In the later proceeding, an ITC administrative-law judge determined in March 2026 that the redesigned implementation did not infringe the Masimo patents at issue there. An administrative-law judge’s determination can be reviewed by the ITC Commission and may be followed by further judicial proceedings. It should therefore be described as a significant decision, not an unreviewable declaration that the entire Masimo-Apple conflict is over. Apple’s account of the proceeding appears in its SEC filing.
Best Value
![Apple Watch Series 11 [GPS 42mm] Smartwatch with Jet Black Aluminum Case with Black Sport Band - S/M. Sleep Score, Fitness Tracker, Health Monitoring, Always-On Display, Water Resistant](https://m.media-amazon.com/images/I/41s72HIk5TL._SL160_.jpg)
- A FULL-FEATURED HEALTH TRACKER—Apple Watch Series 11 gives you invaluable insights about your body, right from your wrist. Take an ECG anytime* and get alerts for a high and low heart rate or an irregular rhythm*—so you can stay closer to your heart. You can also view your overnight health tracking metrics with the Vitals app* and be notified of possible sleep apnea.*
- KNOW YOUR SLEEP SCORE—With advanced sleep tracking, Series 11 gives you a daily sleep score. It’s an easy way to help measure and understand the quality of your sleep, so you can make it more restorative.
- GET HYPERTENSION NOTIFICATIONS—Did you know that Series 11 can spot signs of chronic high blood pressure? By analyzing how your blood vessels respond to beats of the heart, it can notify you of possible hypertension.*
- SAFETY FEATURES—A smartwatch that puts your safety first. Series 11 can detect a hard fall or severe car crash, automatically help connect you with emergency services, and notify your emergency contacts.* Check In can automatically notify a loved one when you’ve arrived at your destination.
- A POWERFUL FITNESS TRACKER—With advanced metrics and motivating features like Pacer, Heart Rate Zones, training load, and Workout Buddy powered by Apple Intelligence from your nearby iPhone*—Series 11 is made to help everyone stay active, from runners and hikers to strength-training enthusiasts.
Masimo’s broader allegations about recruiting employees, confidential information and related court litigation are distinct from the ITC patent-infringement case. They should not be treated as proof of what the import exclusion order covered.
What Blood Oxygen does—and does not—tell you
Apple presents Blood Oxygen as a wellness feature. Apple’s later Apple Watch materials state that measurements are calculated and viewed on iPhone in the Health app (Apple Watch Series 11 newsroom release).
- A reading is not a diagnosis.
- A single wearable result should not replace clinical pulse oximetry or medical advice.
- If symptoms are concerning, use an appropriate medical device and contact a qualified clinician rather than relying on the watch.
Three different questions buyers often confuse
| Question | What it means |
|---|---|
| Is the optical sensor hardware present? | The watch may contain the components used to collect signals. |
| Is Blood Oxygen enabled? | The specific regional unit’s software permits the feature to run. |
| Where is the result calculated and shown? | Original implementations calculated on-watch; the later U.S. redesign sends the calculation to the paired iPhone and displays it in Health. |
Keeping those questions separate avoids the most common buying mistake: assuming a physically equipped watch necessarily offers the same usable Blood Oxygen experience as an earlier or foreign-market unit.
Quick Recap
Product prices and availability are accurate as of the date/time indicated and are subject to change. Any price and availability information displayed on Amazon at the time of purchase will apply.
