Masimo Corp shareholders elected both director candidates proposed by veteran activist investor Quentin Koffey's hedge fund Politan Capital Management, in one of the most contentious boardroom battles of the year.

Masimo (NASDAQ:MASI) rose 3% after activist investor Politan Capital Management won two board seats after a bitter proxy battle with the medical device maker. Politan nominees  Darlene Solomon and William Jellison were elected to the board at a holder vote on Thursday,

"We are united in our enthusiasm for Masimo’s future as a leading, innovation-focused growth company," the newest board members said.