Apple Defends Patent Tribunal Wins Against Masimo on Appeal

Apple Inc. urged an appellate court to leave intact an administrative tribunal’s decision to cancel parts of 13 blood oximeter patents that Masimo Corp. says the tech giant infringed through sales of smart watches.

In oral arguments on Thursday at the US Court of Appeals for the Federal Circuit, a lawyer for Apple said there was substantial evidence supporting a series of Patent Trial and Appeal Board rulings that inventions described in Masimo’s patents were obvious and therefore unpatentable.

The arguments came as part of a broader yearslong legal battle between Apple and Masimo, a medical device company and smart ...