Masimo Sues CBP Over Apple Watch Blood Oxygen Reversal

Masimo challenges CBP over restored Apple Watch blood oxygen feature

Masimo, the medical-technology company that holds patents on pulse oximetry sensors, has filed suit against US Customs and Border Protection (CBP) after the agency reversed a previous restriction tied to an International Trade Commission (ITC) ruling. The dispute centers on Apple’s restoration of blood oxygen tracking to its products — a feature Apple had disabled after a 2023 ITC import ban found that certain Apple Watches infringed Masimo’s patents.

According to Masimo’s complaint, filed this week, CBP failed to notify Masimo before allowing Apple to reactivate the feature. That omission, Masimo says, left it unable to review or challenge the agency’s reversal and deprived the company of an opportunity to protect its patent rights through the usual administrative process.

Apple had previously disabled the pulse oximetry capability on affected Apple Watch models following the ITC decision in December 2023. Last week Apple announced a redesigned approach that calculates blood oxygen on iPhones rather than on the watch. Masimo says the CBP reversal came without meaningful notice and that Apple continues to infringe Masimo’s patents.

Masimo also called attention in its filing to Apple’s recent investments in the United States following failed appeals of the ITC ruling. The complaint alleges the CBP’s new decision “departed substantially from CBP’s established practice regarding LEO ruling requests,” and that the ruling unfairly harms Masimo’s competitive position in the U.S. market.

Masimo is asking the court for emergency relief: a temporary restraining order and a preliminary injunction that would restore the original import restriction and prevent Apple from shipping devices with the restored blood oxygen functionality unless the infringing technology is disabled.

Why this matters for wearables and supply chains

This dispute highlights how intellectual property rulings can ripple through device makers, distributors, and retailers. When an import ban or enforcement decision changes, it can affect product launches, inventory planning, and contractual commitments to suppliers and carriers. For companies that build health features into consumer wearables, the options are generally: litigate, license, or engineer around the patent.

For regulators and customs officials, this case raises questions about due process and consistency in how CBP handles reversals of ITC-related import restrictions. For competitors and partners, it is a reminder that enforcement actions can be resurrected or relaxed based on agency judgments — sometimes with little public notice.

What Masimo wants from the court

In plain terms, Masimo is asking the court to:

• Temporarily block CBP’s reversal so Apple cannot ship devices with the restored feature.
• Reinstate the original ITC-based import restriction unless infringing technology is fully disabled.
• Require CBP to follow established notice and review procedures before granting such reversals.

The case will be closely watched by companies that embed regulated medical or health-adjacent features into consumer devices. A court decision could clarify how strictly customs and trade remedies must adhere to notice procedures and whether agencies can quickly change enforcement outcomes without alerting affected patent holders.

For now, Apple has signaled its intent to restore user-facing blood oxygen capabilities under a redesigned workflow, while Masimo presses for judicial relief. Expect brisk legal filings and potential emergency hearings as both sides race to protect market positions and clarify how IP enforcement interacts with customs and trade policy.