The shake-up announced Tuesday continues a drastic makeover of Yahoo's leadership during the past month as the company tries to win back investors frustrated with years of broken turnaround promises.
Yahoo Inc. ushered in a new era last month by hiring former PayPal executive Scott Thompson as its fourth CEO in less than five years.
Then Yahoo co-founder Jerry Yang resigned from the board.
Bostock is departing along with Vyomesh Joshi, Arthur Kern and Gary Wilson.
Many Yahoo shareholders have been clamoring for Bostock to step down since the company balked a $47.5 billion takeover offer from Microsoft Corp. in 2008.