Masimo does not have an overarching patent on pulse oximetry, as the overarching technology is several decades old. There are many manufacturers of sensors bei

Masimo does not have an overarching patent on pulse oximetry, as the overarching technology is several decades old. There are many manufacturers of sensors being used in many applications with various implementations, many of which are not covered by Masimo's patents. Masimo could not write a patent to cover significantly more implementation variations because they would not be granted the patent in that case. Masimo does have patents on specific implementations of pulse oximetry and sued Apple for implementing specific patented features. This made their legal case pretty solid, but it also made it possible for Apple to continue providing pulse oximetry as long as they avoided the specific IP owned by Masimo.