Apple Hit With $634 Million Verdict in Apple Watch Blood Oxygen Patent Lawsuit

A U.S. federal jury has ruled that Apple owes medical technology company Masimo $634 million for patent infringement related to the blood oxygen-sensing technology in the Apple Watch, reports Reuters. Apple will appeal the verdict.

"We are pleased by this outcome, and appreciate the time and attention given to our case by the court and the jury," said Masimo in a press release." This is a significant win in our ongoing efforts to protect our innovations and intellectual property, which is crucial to our ability to develop technology that benefits patients. We remain committed to defending our IP rights moving forward."

"Over the past six years (Masimo has) sued Apple in multiple courts and asserted over 25 patents, the majority of which have been found to be invalid," an Apple spokesperson told Reuters. "The single patent in this case expired in 2022, and is specific to historic patient monitoring technology from decades ago."

The patent dispute led to a ban on U.S. sales of Apple Watch with the blood oxygen feature in December 2023. Apple was able to temporarily continue selling the Apple Watch models while an interim stay was in place during an appeal, but the ban was reinstated as of January 18, 2024, and Apple addressed the issue by immediately launching sales of models with the feature disabled in software.

Apple Watch models in the U.S. remained unable to support blood oxygen monitoring for over a year and a half before Apple introduced a workaround in August 2025 with blood oxygen data being processed and displayed on a paired iPhone rather than on the Apple Watch itself, a change that satisfied U.S. Customs regulators that had been charged with enforcing the original ban.

Apple's workaround did not sit well with Masimo, which filed another lawsuit in an attempt to overturn the U.S. Customs decision and once again prevent Apple from selling Apple Watch models with the blood oxygen feature in the U.S., but there has yet to be a ruling in that lawsuit.