Apple’s requests to overturn a $634 million patent verdict and secure a new trial in its long-running legal battle with Masimo were denied. Here are the details.
A bit of background
In early 2020, medical technology company Masimo sued Apple, accusing it of stealing trade secrets and infringing patents related to pulse oximetry and other optical health-monitoring technologies used by the Apple Watch.
Since then, the companies have been locked in a sprawling legal battle. In 2023, Masimo secured an International Trade Commission (ITC) ruling that led to a US import ban affecting Apple Watch models equipped with blood oxygen monitoring.
This prompted Apple to temporarily halt sales, later resuming sales of affected models with the blood oxygen feature disabled. In 2025, the company introduced a redesigned feature that measures and calculates sensor data from the Apple Watch on the paired iPhone, with results displayed in the Health app. Masimo subsequently sued US Customs and Border Protection over its decision to allow imports of watches featuring the redesign.
Meanwhile, the patent portion of Masimo’s original California lawsuit proceeded separately from the ITC case. In November 2025, a jury found that the Apple Watch’s heart-rate monitoring and notification features infringed a different Masimo pulse oximetry patent and ordered Apple to pay $634 million in damages.
Since then, Apple has been attempting to overturn this finding, which brings us to today.
Judge upholds the jury’s findings
As reported by Law360 (via AppleInsider):
In his ruling, Judge Selna sided with the jury’s conclusion that the Apple Watch can be considered a patient-monitoring device under the patent. Apple had basically argued that the term should apply only to conventional medical equipment, but the judge found that the patent’s broader, everyday meaning could also cover the Apple Watch.
He also rejected Apple’s request for a new trial. Apple had challenged the jury instructions and the decision to exclude testimony from one of its experts, but Judge Selna found no errors serious enough to warrant a retrial.
When reached for comment, Apple referred Law360 to an earlier statement, which said:
To read Law360’s full report, follow this link.
