58003
The activist hedge fund, which has been pushing for changes at Yahoo since 2014 and owns about 1.7 percent of the company, said it would nominate nine candidates for the board.
The proxy fight comes as Yahoo is pressing ahead with an auction of its core Internet business, which includes search, mail and news sites. The faded Internet pioneer has been struggling to keep up with Alphabet Inc.'sGoogle and Facebook Inc. in the battle for online advertisers.
"It is unfortunate that this action is necessary," Starboard said in a letter to Yahoo shareholders.
"We have been extremely disappointed with Yahoo's dismal financial performance, poor management execution, egregious compensation and hiring practices, and general lack of accountability and oversight by the board."
However, Starboard said it remained open to discussions with Yahoo and was hopeful that it could reach an agreement to get involved with the company.
Some Yahoo investors are concerned that a proxy fight would hinder the auction effort, sowing doubts among potential buyers over the stability of the board, sources have said.
Yahoo's shares, which have fallen about 22 percent in the past 12 months, were flat at $34.76 in premarket trading.
Yahoo launched an auction of its core business in February after it shelved plans to spin off its stake in Chinese e-commerce giant Alibaba Group Holding Ltd.
Starboard's nominees include its chief executive, Jeffrey Smith, and Eddy Hartenstein, the former chief executive of Tribune Co.
Yahoo could not be immediately reached for comment.
The Wall Street Journal first reported on Wednesday that Starboard would launch the proxy contest.
(Reporting by Supantha Mukherjee in Bengaluru; Editing by Anupama Dwivedi and Ted Kerr)