Representatives from Facebook, Microsoft and Google all declined to comment on the talks.

The investment discussions by Facebook are part of its effort to raise an additional round of capital to further the company’s growth and build on its current momentum. The company has solicited interest not only from Internet companies but also from a handful of financial players including venture capitalists, hedge funds and private equity firms, according to people with knowledge of its plans.

Facebook is seeking a minimum valuation of $10 billion but interested bidders have expressed a willingness to value it as high as $13 billion, on the assumption that, in the future, Facebook will become a powerful player in the online world.

These numbers might have little basis in actual revenue or profit. Facebook is a private company and does not reveal its income. But earlier this year, a Pali Research analyst, Richard Greenfield, estimated that the company brought in $60 million to $96 million in annual revenue, with no real profit. Much of that revenue comes from a year-old advertising relationship with Microsoft, which places display advertisements on the site.

Mr. Greenfield said the investment price that Microsoft was considering might have more to do with keeping the prize out of the hands of its powerful rivals. “There may be competitive reasons to be connected to this asset beyond what the specific valuation is today,” he said. “You may be paying a premium to keep others out.”

The lack of a track record for Facebook might actually be driving the price up. “Trying to delineate a value today of what was a new industry five years ago is challenging right now,” Mr. Greenfield said.