Groupon shares shed over 15 percent to close below their initial public offering price on Wednesday, less than three weeks after the online daily deals site made its debut on Wall Street.
Groupon shares, which were listed on the Nasdaq at $20 on November 4, finished the day at $16.96, a loss of $3.11 or 15.5 percent on the day.
Shares of the Chicago-based company soared as high as $31.14 on the first day of trading but they have lost ground since then, shedding more than 30 percent of their value since Friday.
"Apparently investors have figured out that there are other companies competing hard in the same space and that there are few barriers to keep more competitors out," the website 247WallSt.com said of Groupon's slide.
Internet giant Google and LivingSocial are among the firms offering online discounts similar to those proposed by Groupon.
Groupon, which rejected a $6 billion takeover offer from Google a year ago, has enjoyed phenomenal growth since its founding in 2008 but has been dogged by questions about its business model and accounting methods.
Groupon raised $700 million in the biggest initial public offering by an Internet company since Google, which reaped $1.7 billion when it went public in August 2004.
Groupon, which is present in 175 North American markets and 45 countries, reported a net loss of $308.1 million for the first nine months of this year compared to a loss of $77.7 million during the same quarter last year.
Revenue soared to $1.1 billion in the same period from $140.7 million a year ago.