Continued reports that Yahoo Inc. is lining up allies in its attempt to fend off Microsoft Inc.'s pursuit of its online search engine business sent shares of the Internet pioneer higher in premarket trading Thursday.

Even though Yahoo!'s board opted to side with Google in its eagerness to shrug of Microsoft's advances, the company may not be out of the woods quite yet. Mark Nelson, a partner in Mithras Capital, which owns 1.7 million Yahoo shares has written to Microsoft urging the company to reconsider its partial deal for Yahoo!'s search engine business.