Chinese online games publisher Giant Interactive (NYSE: GA) is acquiring about 25 percent stake in Five One Network Development (51.com), a Chinese online social networking service provider, for approximately $51 million. Rumors to this effect had been circulating for a while now.

Founded in 2005, 51.com claims to be the largest independent social network service provider in China in terms of its total number of registered users. As of June 15, 2008, the total number of registered users on 51.com was approximately 120 million and monthly unique visitors were approximately 31.5 million.  In addition, monthly unique visitors logged in 18 times per month on average and average daily page views were approximately 350 million. Giant joins investors such as early lead investor Sequoia Capital China, and following round investors SIG, Intel (NSDQ: INTC) Capital, and Redpoint Ventures in its investment in 51.com.

This investment will allow Giant an opportunity to broaden its player base, expand its community-building opportunities and extend the lifecycles its games.

Giant is the third-largest online games company in China with net revenues of $209.4 million and net income of $155.8 million in 2007. Some more details in release.

This story has been provided by our research partner Pearl Research.

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