Hewlett-Packard's Interim Chairman Ralph Whitworth has resigned from the company's board to concentrate on personal health issues.
Whitworth's resignation is effective on Wednesday. Personal computer maker HP said that its board will discuss appointing a new chairman at its next meeting.
Whitworth became HP's interim chairman in April 2013 after former chairman Ray Lane stepped down from his post. At the time that Lane stepped down, HP also announced that directors John Hammergren and G. Kennedy Thompson were leaving the board. The shake-up was spurred by disgruntled stockholders unhappy with HP's performance.
Whitworth, an activist shareholder, has served as an HP board member since 2011.
He is also taking a leave of absence from the privately held investment company he co-founded, Relational Investors.
Hewlett-Packard Co. is based in Palo Alto. Its stock fell 14 cents to $34.01 in premarket trading on Tuesday.