Apple Secures Major Legal Victory as ITC Rejects Masimo Bid to Ban Redesigned Apple Watch Models

The International Trade Commission has formally declined to review an earlier judicial ruling that favored Apple Inc. in its long-standing patent dispute with the medical technology firm Masimo, effectively ending a significant threat to the continued sale of Apple Watch models in the United States. This decision marks a pivotal moment in a multi-year legal saga that has seen product bans, technical redesigns, and a fundamental challenge to how consumer electronics companies integrate medical-grade sensors into wearable devices. By terminating the investigation and upholding the finding of non-infringement for Apple’s redesigned blood oxygen monitoring feature, the Commission has provided Apple with a clear path forward for its primary wearable lineup, though the possibility of a federal appeal remains on the horizon for Masimo.

The ITC Ruling and the End of the Enforcement Proceeding

The conclusion of this specific chapter of the litigation stems from a decision by the full International Trade Commission (ITC) to not review an Initial Determination issued by an Administrative Law Judge (ALJ) on March 18, 2026. That earlier ruling, known as an Enforcement Initial Determination (EID), concluded that Apple’s redesigned software architecture for the blood oxygen feature—which shifted a significant portion of the data processing from the watch hardware to the connected iPhone—did not infringe upon the specific pulse oximetry patents held by Masimo.

In the legal document released today, the Commission noted that after reviewing petitions filed by both Masimo and Apple on March 25, 2026, and subsequent responses on March 30, it determined that the ALJ’s findings were sound. The decision states: "The Commission has determined not to review the EID. This combined proceeding is hereby terminated in its entirety with the conclusion that the accused redesigned products do not infringe the Asserted Patents, and therefore, they should not be excluded pursuant to the terms of the LEO [Limited Exclusion Order]."

This ruling effectively validates Apple’s technical workaround. To circumvent a previous import ban, Apple had modified the Blood Oxygen app on Series 9, Ultra 2, and subsequent models sold in the U.S. market. By decoupling the local processing on the watch and utilizing the iPhone’s processor to interpret the sensor data, Apple successfully argued that it was no longer utilizing the specific methods protected by Masimo’s intellectual property.

A Chronology of the Apple-Masimo Conflict

The dispute between the Cupertino-based tech giant and the Irvine-based health firm is one of the most contentious in the history of wearable technology. To understand the gravity of the recent ITC victory, one must look back at the timeline of the conflict:

• 2013-2014: Apple reportedly contacts Masimo to discuss potential collaborations regarding health sensors. Masimo later alleges that Apple used these meetings to identify and poach key talent, including Masimo’s Chief Medical Officer.
• September 2020: Apple launches the Apple Watch Series 6, the first model to feature a blood oxygen (SpO2) sensor.
• January 2021: Masimo files a lawsuit against Apple in the U.S. District Court, alleging trade secret theft and patent infringement.
• June 2021: Masimo files a formal complaint with the ITC, seeking to block imports of the Apple Watch.
• October 2023: The ITC rules in favor of Masimo, finding that Apple violated Masimo’s patents related to light-based pulse oximetry. A Limited Exclusion Order is issued.
• December 2023: Apple briefly pauses sales of the Apple Watch Series 9 and Ultra 2 in the U.S. to comply with the looming ban.
• January 2024: U.S. Customs and Border Protection rules that Apple’s proposed redesign (disabling or modifying the feature) allows the watches to bypass the ban. Apple begins selling watches with the Blood Oxygen feature disabled or altered via software.
• August 2025: Apple introduces a redesigned version of the blood oxygen feature that relies on iPhone-side processing, attempting to re-enable the functionality for U.S. users legally.
• March 2026: An ITC Administrative Law Judge rules that the redesign does not infringe on Masimo’s patents.
• April 2026: The full ITC Commission declines to review the ALJ’s decision, finalizing the victory for Apple’s redesign.

Technical Context: The Science of Pulse Oximetry

At the heart of the legal battle is pulse oximetry technology. This health feature measures the percentage of oxygen carried by red blood cells from the lungs to the rest of the body. In the Apple Watch, this is achieved through a cluster of four LED clusters and four photodiodes on the back crystal. Green, red, and infrared LEDs shine light onto the blood vessels in the wrist, and the photodiodes measure the amount of light reflected back.

Masimo, a leader in hospital-grade pulse oximeters, claimed that Apple’s implementation of this sensor and the algorithms used to interpret the light data infringed on patents they had spent decades developing. The "redesign" that Apple implemented was a sophisticated software pivot. By changing the sequence of data transmission and ensuring the "calculation" of the blood oxygen percentage occurred on a separate device (the iPhone), Apple moved the functionality outside the literal scope of Masimo’s patent claims, which often specified the processing occurring within the "wearable device" itself.

Statements from the Parties

Following the ITC’s decision, Apple released a statement expressing satisfaction with the outcome while taking a sharp tone toward its opponent. "We thank the ITC for its decision, which ensures we can continue to offer this important health feature to our users," a spokesperson for Apple said. "For more than six years, Masimo has waged a relentless legal campaign against Apple, and nearly all of its claims have been rejected. We will always defend our innovations, and remain focused on what we do best: delivering the best products and services in the world for our users."

Apple further emphasized its commitment to the health space, noting that the Blood Oxygen feature sits alongside a suite of other life-saving technologies, including the ECG app, high and low heart rate notifications, and the more recently introduced sleep apnea detection and hypertension monitoring features.

Masimo, led by CEO Joe Kiani, has historically maintained that Apple’s actions represent a "predatory" approach to innovation, where a larger company simply absorbs the intellectual property of a smaller pioneer. While Masimo has not yet issued a formal response to today’s specific termination of the review, the company retains the right to appeal the ITC’s final decision to the U.S. Court of Appeals for the Federal Circuit. Legal analysts suggest that given Masimo’s persistence over the last half-decade, an appeal is highly probable.

Market and Financial Implications

The Apple Watch is the cornerstone of Apple’s "Wearables, Home, and Accessories" segment, which generates billions of dollars in quarterly revenue. During the initial ban in late 2023, analysts estimated that a prolonged exclusion from the U.S. market could have cost Apple between $300 million and $500 million in lost sales during the critical holiday quarter.

Beyond the immediate financial impact, the ability to offer blood oxygen monitoring is a competitive necessity. Rivals such as Samsung, Garmin, and Google (Fitbit) all offer SpO2 monitoring as a standard feature. Had Apple been permanently forced to disable the feature in its home market, it would have faced a significant disadvantage in the health-tracking sector, which has become the primary driver of smartwatch adoption.

This victory also serves as a case study in "design-around" strategies in patent law. Apple’s success in convincing the ITC that a software-based architectural shift constitutes a non-infringing product could provide a blueprint for other tech companies facing similar hardware patent disputes.

Broader Impact on the Wearable Health Industry

The resolution of this case (at the ITC level) suggests a shifting boundary between consumer electronics and regulated medical devices. As companies like Apple, Amazon, and Google push deeper into health diagnostics, they are increasingly colliding with established medical technology firms like Masimo and AliveCor.

The ITC’s decision to accept a software workaround highlights the agency’s willingness to consider the nuances of modern computing architecture. It also underscores the importance of patent drafting; if Masimo’s patents had been written with broader language encompassing "a system comprising a wearable and a mobile device," the outcome might have been different.

For consumers, the ruling means that the Apple Watch Ultra 2, Series 9, and newer models will continue to be available with their full suite of advertised health features. It also clears the regulatory clouds over the upcoming "Apple Watch Series 11" and future iterations, allowing Apple’s engineers to continue refining their health-sensing hardware without the immediate threat of a border seizure.

Future Outlook

While Apple has won this round at the ITC, the legal war is not entirely over. There is still the potential for a jury trial in district court regarding trade secret allegations, and as mentioned, the appellate process for the ITC ruling. Furthermore, the relationship between big tech and medical pioneers remains strained.

For now, the "Blood Oxygen" icon will remain active on millions of wrists across the United States. Apple’s focus will likely shift to its next frontier: non-invasive glucose monitoring, a "holy grail" of health tech that is rumored to be in development. Given the precedent set by the Masimo case, Apple will undoubtedly be taking even greater care to ensure its future sensors are backed by an impenetrable fortress of its own patents and unique software architectures.