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One of China’s biggest social networking websites has made its stock market debut on the New York Stock Exchange for more than $700m. Renren has about 30 million regular users in China.
    Renren was set up by three classmates at a Chinese university in 2005. Its site resembles Facebook, and its origins are also similar. But is it really worth $5 billion? The opening price was set higher than seemed likely a few days ago, and the shares shot up nearly 40% from that level in the first hours of trading. This despite the fact that Renren was forced to backtrack on claims that it has over 100 million subscribers.