Groupon is one of a couple of highly anticipated IPOs that have been delayed since late summer's wave of highs and lows in the stock market following questions about the strength of European economies, the downgrading of the U.S. debt by Standard and Poors, and fears of a double dip recession.

Social gaming site Zynga has also delayed a much anticipated IPO over the same market concerns.

The deals site initially filed with the Securities and Exchange Commission for a $750 million public offering in June, but recent market volatility has made the market environment more difficult, according to Reuters sources.

Online and tech-savvy company IPOs have been closely watched by investors ever since the enormous performance of professional social networking site LinkedIn on its first day of public trading earlier this summer.

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