Masimo Files Lawsuit Against U.S. Customs to Reinstate Apple Watch Blood Oxygen Monitoring Ban, Contesting Apple’s iPhone Workaround Feature

Masimo, a prominent medical device manufacturer, has taken legal action against U. S.Customs and Border Protection (CBP) concerning the reinstatement of the Blood Oxygen monitoring feature on the Apple Watch. The lawsuit asserts that CBP has exceeded its authority by allowing imports of Apple Watch models equipped with this feature, which Masimo argues violates established procedural regulations. This development comes shortly after Apple launched iOS 18.6.1, integrating a workaround for the Blood Oxygen Monitoring feature via the iPhone, raising objections from Masimo.

Masimo Challenges Apple Watch Features: A Legal Battle Unfolds

The conflict between Apple and Masimo traces back to December 2023, when the U. S.International Trade Commission (ITC) ruled that Apple had infringed on Masimo’s patents for pulse oximetry technology. Following this ruling, an import ban was enacted, barring the sale of Apple Watch Series 9 and Ultra 2 models with the Blood Oxygen feature in the U. S.In an effort to comply with the ban, Apple implemented software updates that temporarily disabled the feature, allowing continued sales without breaching the patent regulations.

However, as soon as Apple reactivated the Blood Oxygen feature using a workaround, Masimo moved swiftly, requesting a temporary restraining order and a preliminary injunction to nullify CBP’s recent ruling. The company argues that every day this ruling stands inflicts irreparable harm to its market competitiveness in the U. S., as reported by Bloomberg Law. Masimo further contends that CBP’s decision undermines the ITC’s exclusion order, effectively stripping the protective shield off its patented technology.

It has now come to light that CBP thereafter reversed itself without any meaningful justification, without any material change in circumstances, and without any notice to Masimo, let alone an opportunity for Masimo to be heard. CBP changed its position on Apple’s watch-plus-iPhone redesign through an ex parte proceeding. Specifically, on August 1, 2025, CBP issued an ex parte ruling permitting Apple to import devices that, when used with iPhones already in the United States, perform the same functionality that the ITC found to infringe Masimo’s patents. Masimo only discovered this ruling on Thursday, August 14, 2025, when Apple publicly announced it would be reintroducing the pulse oximetry functionality through a software update.

The outcome of this lawsuit could have significant repercussions for the technology and medical sectors. It underscores the ongoing struggle between patent rights, regulatory practices, and technological advancement. Stakeholders are keenly observing how these events will unfold. What do you think? Will Apple retract the workaround that enables Blood Oxygen Monitoring via the iPhone and Apple Watch? Share your opinions in the comments below!

Source & Images