Eight years after its launch, social networking giant Facebook is poised to file papers for an initial public offering seeking to raise at least $5 billion.
The prospectus for an IPO could be filed with the US Securities and Exchange Commission (SEC) as early as Wednesday morning, according to US media reports, although they stressed there was still a possibility it could be delayed.
The Wall Street Journal broke the news of Facebook's impending IPO last week, saying the Palo Alto, California-based company planned to raise $10 billion at a valuation of between $75 billion and $100 billion.
The $10 billion target had been halved to a more conservative $5 billion in reports emerging late Tuesday in The New York Times and International Financing Review.
The publications stressed, however, that $5 billion was only a preliminary fund-raising target and could always be raised after gauging investor interest.
The initial IPO filing was not expected to specify how many shares were being offered or their list price.
It would also not put a valuation on the company nor identify which exchange Facebook shares would be traded on -- the Nasdaq stock market or the New York Stock Exchange.
In any case, Facebook shares are not expected to begin trading until at least May, once the IPO process is finalized.
With a deal size of $10 billion, Facebook would slip into sixth place on the list of largest US IPOs between AT&T Wireless Group ($10.62 billion) and Kraft Foods ($8.68 billion), according to Renaissance Capital.
Even at $5 billion, it would still be the largest IPO ever by a US Internet company, surpassing that of Google which raised $1.9 billion in 2004 and valued the Web search giant at $23 billion.
A market capitalization of $100 billion would put Facebook on a par with McDonald's ($101 billion), well ahead of Boeing ($55 billion) but behind Apple ($426 billion) and Google ($189 billion).
A Facebook IPO would be "the biggest financial event in the tech industry for 2012," Forrester Research analyst Josh Bernoff said, and would eclipse those of several other Internet companies that went public in 2011.
Career-oriented social network LinkedIn was undervalued while online daily deals site Groupon and social games titan Zynga have both been trading at or below their list price.
Facebook chief executive Mark Zuckerberg has deflected IPO talk for years, saying he is focused on building the company and not on going public.
But Zuckerberg, who launched Facebook from his Harvard University dorm room in February 2004 and has seen it grow to more than 800 million members, has recently seemed to bow to the inevitability of selling stock to the public.
Morgan Stanley is expected to be the lead bank for the IPO and IFR said Goldman Sachs, Bank of America Merrill Lynch, Barclays Capital and JP Morgan would also play a role.
According to eMarketer, Facebook's global revenue was $4.27 billion last year, mostly from online advertising.