Starboard Value LP is taking initial steps toward a potential proxy fight with Yahoo! Inc., signaling the activist investor isn't satisfied with the Web portal's latest efforts to streamline and a pledge to consider selling assets, according to people familiar with the matter. Okapi Partners LLC, a proxy-solicitation adviser typically used by Starboard, has been calling Yahoo shareholders, said the people, who asked not to be identified because the process isn't public. Firms such as Okapi often make these calls ahead of a potential proxy battle, and Starboard could push for new board members as soon as this month. The investor owned less than 1 percent of Yahoo's stock at the end of last year.