How much is Facebook worth? The company was projected to surpass $3 billion in revenue in 2011, but it is expected to reach a valuation of up to $100 billion by the time of its initial public offering later this year.

When Facebook files a prospectus for an I.P.O. with the Securities and Exchange Commission, it is not obligated to give any indication about how much money the social network seeks to raise in the public stock sale or the size of the offering.

But there are other ways assess Facebook’s value. Before a company goes public, stocks are bought and sold on secondary private markets. Trading of Facebook on Sharespost currently values the company at more than $82 billion. The chart below shows how the company’s valuation has grown over time based on investments.

DATE VALUATION INVESTORS
All figures through Jan. 31, 2011.
January 2012 $83.5 billion Value based on private secondary markets.
March 2011 T. Rowe Price invests $190.5 million through various funds for a stake less than 1 percent.
March 2011 $65 billion General Atlantic purchases shares from former Facebook employees for a 0.1 percent stake, CBC reports.
February 2011 $52 billion Kleiner Perkins Caufield & Byers invest $38 million for a stake less than 1 percent, The Wall Street Journal reports.
January 2011 $50 billion Goldman Sachs and DST Global get a 1 percent stake for $500 million. Goldman’s overseas clients also invested $1 billion.
June 2010 $23 billion Elevation Partners spends $120 million for shares in the secondary market for 1.5 percent stake.
May 2009 $10 billion Digital Sky Technologies (later DST Global and Mail.ru) invests $200 million for a 2 percent stake.
January 2008 European Founders Fund invest $15 million.
March 2008 $15 billion Li Ka-Shing invests a second $60 million for a total stake of 0.8 percent.
November 2007 Li Ka-Shing invests $60 million.
October 2007 $15 billion Microsoft pays $240 million for a 1.6 percent stake.
September 2006 $900 million Offer by Yahoo that was turned down.
June 2006 Interpublic buys a 0.5 percent stake for less than $5 million.
April 2006 $500 million Greylock Partners, including Meritech Capital Partners, the Founders Fund and Accel invest $27.5 million for a 1.5 percent stake.
January 2006 $750 million Offer from Viamcom that was rebuffed.
April 2005 $100 million Accel Partners pays $12.7 million for a 15 percent stake. Jim Breyer also puts up $1 million of his own money.
February 2005 Maurice Werdegar of WTI Partner provides a second $300,000 credit line and a $25,000 equity investment.
October 2004 Mr. Werdegar provides a $300,000 three-year credit line.
2004 Peter Thiel puts up $500,000 for a loan, later converted to a 10 percent stake and eventually reduced to 3 percent. Mr. Thiel also brings in Reid Hoffman and Mark Pincus.

Who Are the Investors?

Peter Thiel Facebook’s first outside investor and a co-founder of PayPayl is the founder of the hedge fund Clarium Capital Management. Read more »

WTI Partner Western Technology Investment specialized in short-term loans to start-ups. Sean Parker, Facebook’s first president, had a prior relationship with Maurice Werdegar of WTI.

Accel Partners Jim Breyer, a partner at the Silicon valley venture capital firm, was an early investor in Facebook. At the time, his investment was seen as risky, but it may ultimately earn Mr. Breyer and his partners 10 times their original investment. Read more »

Greylock Partners In 2006, David L. Sze, a venture capitalist at Greylock Partners, invested a large portion of the venture money that Facebook raised from Greylock, Meritech Capital Partners, the Founders Fund and Accel. Read more »

Interpublic Interpublic owns advertising and communications agencies like Deutsch, Initiative, McCann Erickson, Mullen and R/GA. In 2011, the company sold half its stake in Facebook for about $130 million. Read more »

Microsoft The company won a high-profile battle with Google and Yahoo to invest in Facebook. The deal was in part about preventing Google from dominating the race to serve advertisements online. Read more »

Li Ka-Shing The Hong Kong developer and business tycoon is one of the wealthiest men in the world. He controls Hutchison Whampoa, one of Asia’s largest companies. Read more »

European Founders Fund Three German Internet entrepreneurs, the Samwer brothers, made their name in 1999 when they sold the German Internet auction site Alando.de to eBay for $50 million in stock. Read more »

DST Global The Russian investment company previously known as Digital Sky Technologies began investing in Internet companies in Russia and Eastern Europe in 2005. The company’s chief, Yuri Milner, is bankrolled by Alisher B. Usmanov, a coal and steel mogul with ties to the Kremlin. One of their earlier successes was Mail.ru, a Russian-language e-mail service and collection of Web properties. DST started the trend of large late-stage investments, sometimes called growth capital. Read more »

Elevation Partners The millions invested by the private equity firm in Silicon Valley went to buying shares owned by Facebook’s employees or early investors. “The private market is emerging as a substitute for what used to be done only in the public markets,” said Marc Bodnick, a managing director at Elevation Partners. Read more »

Goldman Sachs The investment bank helped Facebook raised more than $1.5 billion in new financing, including more than $1 billion from wealthy Goldman clients based overseas. Goldman withdrew the offering from its American clients after the plan drew regulatory scrutiny. Read more »

Kleiner Perkins Caufield & Byers The private equity firm based in Silicon Valley.

General Atlantic The private equity firm run by William E. Ford.

T. Rowe Price The company has made several recent investments in social media companies, including Facebook and Zynga.

The post “Tracking Facebook’s Valuation” first appeared on DealBook