(Reuters) - Apple ( AAPL ) urged a U.S. appeals court on Friday to overturn a U.S. trade tribunal's decision to ban imports of some Apple Watches in a patent dispute with medical-monitoring technology company Masimo ( MASI ).

Apple ( AAPL ) told the U.S. Court of Appeals for the Federal Circuit that the U.S. International Trade Commission's decision was based on a "series of substantively defective patent rulings," and that Masimo ( MASI ) failed to show it had invested in making competing U.S. products that would justify the order.

Representatives for Apple ( AAPL ) and Masimo ( MASI ) did not immediately respond to requests for comment on the filing.

Irvine, California-based Masimo ( MASI ) has accused Apple ( AAPL ) of hiring away its employees and stealing its pulse oximetry technology after discussing a potential collaboration. Apple ( AAPL ) first introduced pulse oximetry to its Series 6 Apple Watches in 2020.

Masimo ( MASI ) convinced the ITC on Dec. 26 to block imports of Apple's ( AAPL ) latest-edition Series 9 and Ultra 2 smartwatches after finding that their technology for reading blood-oxygen levels infringed Masimo's ( MASI ) patents.

Apple ( AAPL ) temporarily resumed sales of the watches the next day after persuading the Federal Circuit to pause the ban. The appeals court reinstated the ban in January, leading Apple ( AAPL ) to remove pulse oximetry capabilities from watches sold during the appeal, which Apple ( AAPL ) has said could last at least a year.

U.S. Customs and Border Protection separately determined in January that redesigned versions of the watches did not violate Masimo's ( MASI ) rights and would not be not subject to the ban. Masimo ( MASI ) said in a court filing that the watches "definitively do not contain pulse oximetry functionality."

Apple ( AAPL ) told the Federal Circuit on Friday that the ban could not stand because a Masimo ( MASI ) wearable covered by the patents was "purely hypothetical" when it filed its ITC complaint in 2021.

The tech giant also argued that Masimo's ( MASI ) patents were invalid and that its watches did not infringe them.