Okay so it wasn't 10 years of court cases (this is what they said on the Vergecast but that apparently was incorrect) however the saga HAS been going on for 10 years:

This particular story started about 10 years ago when Apple reached out to Masimo about a potential partnership around blood oxygen features on its wearables. Soon after, Apple reportedly poached several Masimo engineers and its chief medical officer.

So 10 years ago, Apple reached out to Masimo about the technology, didn't license it, proceeded to hire several of their engineers and its Chief Medical Officer, and then used the technology anyway after not licensing it and clearly poaching their engineers and CMO for the purposes of copying Masimo's IP. And that's what was proven in this court case, that Apple has been infringing on Massimo's patents because of these facts.