Apple’s long-running legal tussle with medical device maker Masimo over blood-oxygen monitoring technology in its smartwatches has taken a fresh turn, with Masimo now targeting U.S. Customs and Border Protection in a bid to halt imports of Apple’s redesigned feature. This escalation underscores the high stakes in wearable health tech, where patents can dictate market dominance and innovation paths.

The dispute traces back to 2013, when Apple reportedly approached Masimo about potential collaboration on pulse oximetry—the technology for measuring blood-oxygen levels. Masimo alleges Apple poached key employees and infringed on its patents, leading to a 2023 ruling by the International Trade Commission that found Apple in violation. As a result, Apple paused U.S. sales of certain Watch models and disabled the feature via software in new units.

The Redesigned Feature and Customs Clearance

In August 2025, Apple announced a redesigned blood-oxygen monitoring system, claiming it sidestepped Masimo’s patents. According to reports from Ars Technica, the update involved software tweaks that reinstated the capability on select models without hardware changes. U.S. Customs cleared these imports, determining they no longer infringed, which allowed Apple to resume offering the feature.

Masimo swiftly challenged this in a lawsuit filed on August 21, 2025, accusing Customs of improperly greenlighting the imports without adequate review. As detailed in a piece from Engadget, Masimo argues the decision was rushed and seeks to block the feature again, potentially forcing Apple back to square one.

Ongoing Trials and Broader Implications

This isn’t the only front in the battle. A November 2024 California trial saw Masimo claim Apple stole trade secrets by hiring its talent, though Apple won a minor counter-suit for $250, as noted in Tom’s Guide. Posts on X (formerly Twitter) reflect public sentiment, with users like tech analysts speculating on settlement possibilities following Masimo’s CEO resignation in 2024, which some viewed as opening doors to negotiation.

The feud highlights tensions in health tech innovation. Masimo, a leader in hospital-grade pulse oximeters, has criticized Apple’s implementation as unreliable, per a 2024 statement covered by 9to5Mac. Apple maintains its technology is original and respects IP, but the disputes have delayed features and raised questions about consumer access to health monitoring.

Market Impact and Future Outlook

For consumers, the blood-oxygen tool—introduced in the Series 6 Watch—has been a selling point for wellness tracking, especially post-pandemic. Its absence in U.S. models frustrated buyers, pushing some to import or seek alternatives. Now, with the redesign, Apple aims to regain ground, but Masimo’s suit could prolong uncertainty.

Industry insiders see this as a test case for patent enforcement in wearables. A report from The New York Times suggests Apple might pursue licensing deals or further redesigns. Meanwhile, Masimo’s aggressive stance, including the Customs lawsuit reported by BGR, signals no retreat.

As the case unfolds, it could reshape how tech giants integrate medical tech, balancing innovation with IP rights. Apple has continued global sales unaffected, but U.S. resolution remains pivotal. With trials ongoing, a settlement might emerge, potentially allowing both companies to focus on advancing health monitoring rather than litigation.