Masimo Sues U.S. Customs, Accuses Agency of Illegally Helping Apple Bypass Watch Ban

Masimo is taking U.S. Customs and Border Protection to federal court, challenging a recent ruling that allows Apple to re-enable the blood oxygen feature on its latest Apple Watch models. The lawsuit alleges CBP unlawfully reversed a prior decision through a secret process, effectively gutting an International Trade Commission import ban and violating Masimo's due process rights.

The complaint, filed in Washington D.C., claims the medical technology company was given no notice of the proceeding and only learned of the new ruling after Apple publicly announced it was restoring the feature via a software update last week.


The dispute stems from an October 2023 ITC decision that found Apple's watches infringed on multiple Masimo patents related to pulse oximetry technology. After the Biden administration declined to veto the resulting import ban, Apple was forced to sell its latest watches in the U.S. with the feature disabled.

According to the new court filing, CBP conducted a full adversarial proceeding in January 2024, with participation from both companies, and determined that Apple's redesigned watches could be imported only if the infringing functionality was completely disabled. The lawsuit states that Apple later submitted a second redesign proposal that moved the final blood oxygen calculation from the watch to a paired iPhone, a request that was reportedly denied by CBP in January 2025.

Masimo's lawsuit argues that CBP "inexplicably reversed course" in its August 2025 ruling. It claims CBP created a loophole by adopting a "self-imposed rule against considering indirect infringement theories," allowing Apple to import watches that are intended to be paired with iPhones already in the U.S. to perform the infringing function.

The company is asking the court for an injunction to block the August ruling and require CBP to enforce the ITC's exclusion order as it was previously interpreted. Apple's appeal of the original ITC orders is still pending at the U.S. Court of Appeals for the Federal Circuit.


Please download the iClarified app or follow iClarified on Twitter, Facebook, YouTube, and RSS for more updates on the case.