Masimo has filed a lawsuit against the US Customs and Border Protection (CBP) agency, alleging that it should not have allowed the import of Apple watches that were previously found to infringe on Masimo鈥檚 pulse oximetry patents.
The with the US District Court of Columbia highlights findings by the International Trade Commission (ITC) that Apple鈥檚 watches infringed on Masimo鈥檚 patents relating to its light-based pulse oximetry technology, as per an investigation in October 2023. The ITC issued a limited exclusion order (LEO) in light of the findings that prohibited the importation of Apple Watch鈥檚 featuring the technology into the US.
Discover B2B Marketing That Performs
Combine business intelligence and editorial excellence to reach engaged professionals across 36 leading media platforms.
Apple subsequently explored a proposed redesign to see whether it could push its watch鈥檚 oximetry feature outside the LEO鈥檚 scope. In January 2024, the CBP determined, through a process including participation from Apple and Masimo, that Apple鈥檚 redesigned watches could be imported only to the extent the infringing functionality was 鈥渃ompletely disabled鈥�.
However, Masimo alleges that in August 2025 the CBP 鈥渞eversed itself without any meaningful justification鈥� to allow Apple Watch imports with the oximetry functionality to continue. This occurred without giving notice to Masimo, the company claims.
On Apple鈥檚 part, it performed a workaround to the LEO. Apple Watch still collects the raw data to produce a blood oximetry reading. However, Apple allegedly moved the calculation steps that provide the reading to its iPhone handsets and display it there instead of on its Apple Watch.
According to the lawsuit, the CBP has now given the go-ahead for Apple to import devices that, when used with iPhones already in the US, perform the same functionality that the ITC found to infringe Masimo鈥檚 patents.
US Tariffs are shifting - will you react or anticipate?
Don鈥檛 let policy changes catch you off guard. Stay proactive with real-time data and expert analysis.
By GlobalDataMasimo said it only learned of the development on 14 August when Apple publicly announced it was reintroducing the pulse oximetry functionality through a software update.
Masimo鈥檚 lawsuit requests 鈥渄eclaratory and injunctive鈥� from the District of Columbia court. In effect, the company wants the CBP to continue enforcing the ITC exclusion order 鈥渁s properly interpreted鈥� in the CBT鈥檚 prior decision in January 2025.
According to an accompanying statement seen by Bloomberg Law, Masimo stated: 鈥淓ach passing day that this unlawful ruling remains in effect irreparably deprives Masimo of its right to be free from unfair trade practices and to preserve its competitive standing in the US marketplace.鈥�
The legal challenge by Masimo is ongoing, with no timelines to its resolution in sight. For now, Apple鈥檚 workaround appears set to remain in place. However, the patents held by Masimo for the technology at the heart of the dispute expire in 2028.
