Starboard Value last week launched a proxy fight to replace the board at Yahoo, blasting the company’s management and nominating its own slate of board members. One of Yahoo’s largest investors, Starboard has a 1.7 percent stake worth about $570 million. It has been “extremely disappointed with Yahoo’s dismal financial performance, poor management execution [and] egregious compensation and hiring practices,” Jeffrey Smith, managing member of Starboard, said in a letter to Yahoo’s other shareholders.