Guardant Health: Helmy Eltoukhy, AmirAli Talasaz, Meghan Joyce

Helmy Eltoukhy, CEO of Guardant Health, and AmirAli Talasaz, the company's president and chief operating officer, will serve as co-CEOs going forward. Both will also continue to be company directors, and Eltoukhy will assume the role of board chairman.

In addition, Meghan Joyce has been appointed as an independent director of Guardant. She is chief operating officer and executive VP of platform at Oscar Health. Prior to that, she held several roles at Uber Technologies, most recently regional general manager of the US and Canada. She holds a master's degree from Harvard Business School and a bachelor's degree from Harvard College.