Apple overstepped on one of five Masimo patents pertaining to using light sensors to assess the amount of oxygen in the blood, an International Trade Commission (ITC) judge has ruled. According to a report, the ITC issued an initial determination in its inquiry into Masimo and Apple on Tuesday. The ITC judge has ruled that by importing and selling watches with light-based pulse oximetry features and components, Apple infringed on one of Masimo’s pulse oximeter patents. Masimo is a US-based medical technology company that develops patient monitoring devices. The judge ruled that the remaining four Masimo patents had not been violated.

According to an MD+DI report, Masimo welcomed the ITC’s ruling. “We are happy that the [administrative law judge] recognized Apple’s infringement of Masimo’s pulse oximetry technology and took this critical first step toward accountability,” Masimo CEO Joe Kiani said. “Today’s decision should help restore fairness in the market. Apple has similarly infringed on other companies’ technologies, and we believe today’s ruling exposes Apple as a company that takes other companies’ innovations and repackages them.”

Apple, however, has remained defiant despite the ruling. According to a Reuters report, the tech giant released a statement disagreeing with the ITC decision. “We respectfully disagree with today’s decision, and look forward to a full review by the Commission,” Apple said.

It’s worth noting that Apple introduced the blood oxygen monitoring feature with the Apple Watch Series 6 in 2020. According to the MD+DI report, Masimo said that ITC was considering imposing an import ban on Apple Watch models which utilise the same technology.

In recent years, Apple has been embroiled in patent battles with both Masimo and AliveCor, another medical device manufacturer, which specialises in developing ECG hardware and software. Just last month, ITC ruled that Apple had infringed upon AliveCor patents with their electrocardiogram (ECG) feature on Apple Watch models. The commission sought to ban imports of the infringing Apple Watch models, but paused the ban until appeals were completed in a separate dispute.