Microsoft Corp. said it will further tailor its Bing search results with data gleaned from users of Facebook Inc., as Microsoft and the social network deepen their ties.

The plan is a sign of how Microsoft and Facebook are coming closer together at a time when both companies increasingly share a common foe: Google Inc.

Both Microsoft and Google are attempting to use clues derived from Web searchers' online social circles to produce more relevant search results, including endorsements of movies, news articles and anything else on which one can form an opinion. The clues—called "social signals" by Microsoft and Google—are intended to give search engines a more trustworthy way of ranking search results as more traditional methods of crafting them fall victim to manipulation.

But Facebook, the richest source of social information on the Web with over 600 million members, has chosen to share most of its data with Microsoft, not Google. Lisa Gurry, a director of Bing, said the Facebook data Microsoft is tapping into is part of an alliance announced last October that will help differentiate Bing from its larger rival. "We view this as a competitive advantage over Google," Ms. Gurry said.

A Facebook spokeswoman said Google has access to some Facebook data for its search results, but not as much as Bing does. "We are not discussing this specific kind of partnership with other search engines at this time, but we are open to having those discussions with them," the spokeswoman said.