Groupon Inc., the largest Internet daily-deal site, plunged as much as 15 percent in Nasdaq Stock Market trading, pushing the shares near their initial public offering price for the first time.
The stock was dragged down for a second day amid concern that it may struggle to reach profitability because of surging marketing costs and competition from rivals such as LivingSocial.com, backed by Amazon.com Inc.
Groupon stock was buoyed in the days after its IPO because it offered a small percentage of the outstanding shares — holding a so-called low-float IPO — which helped drive up demand. Now investors are having second thoughts, said Howard Lindzon, chief executive officer of the online investing community StockTwits.