Facebook Inc.’s estimated worth is now bigger than EBay Inc.’s valuation, making it the third- largest U.S. Internet business and underscoring the growing allure of social media for investors.

Facebook’s stock is trading at more than $16 on SecondMarket Inc., an exchange for shares of privately held companies, said a person familiar with the latest pricing data. That would put its worth at about $41 billion, more than EBay’s $39.3 billion valuation on the Nasdaq Stock Market. Facebook only trails Amazon.com Inc., worth $74.4 billion, and Google Inc., valued at $192.9 billion, among U.S. Internet companies.

“There is certainly good cause for Facebook to have a tremendous valuation,” said Augie Ray, an analyst at Forrester Research Inc. in San Francisco. “It has in fairly short order — just a couple of years — gone from being a very niche site to one where the majority of Americans spend a great deal of their online time.”

Facebook, the world’s largest social-networking site, previously vaulted past other Internet pioneers, such as Web portal Yahoo! Inc. and travel site Expedia Inc. By providing a platform for people to share everything from baby photos to what they had for lunch, Facebook has attracted more than 500 million users and a horde of advertisers hoping to reach them. It’s also a way for people to stay in touch with friends and form new connections.

(Read More: Bloomberg.com)