Background
The Apple Watch blood oxygen patent dispute between Masimo Corporation and Apple Inc. has been one of the most closely watched ITC patent cases in years. Masimo, a medical technology company, holds patents covering wearable pulse oximetry—the technology that measures blood oxygen levels through the skin. In December 2023, the ITC issued a limited exclusion order (LEO) finding that Apple Watch Series 9 and Ultra 2 models infringed claims 22 and 28 of U.S. Patent No. 10,912,502 and claims 12, 24, and 30 of U.S. Patent No. 10,945,648. Apple was forced to deactivate the blood oxygen feature on new watches sold in the United States.
Rather than accept permanent exclusion, Apple engineered a redesign—dubbed “Redesign 2″—that shifted the blood oxygen calculation from the Apple Watch itself to the paired iPhone. Under the redesign, the Watch collects raw sensor data, but the Health app on the iPhone performs the actual computation and displays the result. Apple sought approval from U.S. Customs and Border Protection and relaunched the feature in August 2025. Masimo challenged this design-around, arguing it still violated the existing exclusion order, triggering a formal enforcement proceeding before ALJ Monica Bhattacharyya.
On March 19, 2026, the Federal Circuit separately affirmed the original ITC exclusion order that found Apple’s prior Apple Watch design infringed Masimo’s patents. One day earlier, ALJ Bhattacharyya had issued her Enforcement Initial Determination (EID) finding that the Redesign 2 Watch did not infringe the asserted patents. Both Masimo and Apple petitioned the full Commission to review the ALJ’s enforcement ruling.
The Court’s Holding
On April 17, 2026, the ITC Commission issued a determination not to review ALJ Bhattacharyya’s EID. By declining review, the Commission adopted the ALJ’s conclusion that Apple’s Redesign 2 Watch “doesn’t directly infringe asserted claims… nor does it induce their infringement when used with an iPhone in the U.S.” The Commission formally terminated the enforcement proceeding, concluding: “The accused redesigned products do not infringe the Asserted Patents, and therefore, they should not be excluded pursuant to the terms of the Limited Exclusion Order.”
The key to the non-infringement finding was Apple’s architectural shift. By relocating the blood-oxygen calculation to the iPhone rather than performing it on the Watch, Apple placed the accused functionality outside the scope of Masimo’s claims. The original patents covered devices that independently measured and reported physiological data; Apple’s redesign essentially made the Watch a data-collection peripheral, with the computation—and therefore the alleged infringement—occurring on a separate device not subject to the exclusion order.
Key Takeaways
- Design-arounds at the ITC can succeed even after an exclusion order is affirmed on appeal, so long as the redesigned product falls outside the specific asserted patent claims rather than merely making cosmetic or trivial changes.
- Splitting functionality between devices—collecting data on one and processing it on another—can be a viable non-infringement strategy when patent claims require both functions to occur on the same device.
- The ITC’s enforcement proceeding is a separate track from Federal Circuit appeals of the original exclusion order; an affirmed exclusion order covers the original product, but a design-around receives fresh analysis in enforcement proceedings.
- Masimo may still appeal the Commission’s enforcement determination to the Federal Circuit, though with the original patents expiring in 2028, the practical window for relief is narrowing.
Why It Matters
This ruling ends one of the most prominent ITC patent battles of the decade, allowing Apple to continue selling Apple Watch models with a blood oxygen feature in the United States. For Apple, it validates the strategy of engineering around an exclusion order rather than paying licensing fees—a path that required both technical creativity and regulatory navigation. For Masimo, the result is a disappointing end to litigation that once seemed to hand it leverage over one of the world’s most valuable consumer electronics franchises.
More broadly, the case illustrates both the power and the limits of ITC Section 337 proceedings. The ITC can impose swift import bans, but determined respondents with the resources to redesign their products can escape exclusion if they can demonstrate that the new design falls outside the asserted claims. As hardware increasingly relies on software and cloud or companion-device processing, splitting computation across devices may become a standard patent design-around strategy—one that courts and the ITC will need to evaluate with increasing frequency.