Masimo Corp. filed suit in the U.S. District Court for the District of Columbia on 20 August, accusing U.S. Customs and Border Protection of exceeding its authority by allowing Apple Inc. to import Apple Watches that once again offer blood-oxygen monitoring. The complaint says an internal CBP ruling issued on 1 August cleared the devices without notifying Masimo, overturning a January 2024 determination that had kept the feature disabled. Apple disclosed on 14 August that a forthcoming software update would restore the blood-oxygen function by shifting data processing to a paired iPhone, a change it said was sanctioned by CBP. Masimo argues the agency’s ex parte decision violated the Administrative Procedure Act and the Fifth Amendment, and is seeking a temporary restraining order and preliminary injunction to block the ruling and halt sales of watches with the reactivated capability. The dispute stems from an October 2023 International Trade Commission exclusion order that barred imports of Apple Watch Series 9 and Ultra 2 after the ITC found Apple infringed Masimo’s pulse-oximetry patents, Nos. 10,912,502 and 10,945,648. Apple is appealing the ITC decision, while separate infringement and trade-secret cases between the two companies continue.