Groupon, which sells discounts on everything from foot spas to haute cuisine online, priced its shares at $20 (12.50) each in New York on Thursday – above the initial range of $16 to $18 – and increased its offering by 5m shares to value the three-year-old internet firm at $13bn,The Guardian reported.Groupon, the online discount coupon company, has become the biggest internet flotation since Google, after it raised $700m (£437m) in an eagerly awaited initial public offering.

The $700m flotation ranks Groupon as the largest internet IPO since Google raised about $1.7bn in 2004. Groupon shares will go public on the Nasdaq stock exchange on Friday, the Guardian said.

Groupon has faced months of criticism from regulators and analysts, raising doubts as to whether the company would go public at all.

Research by published in September said that Groupon’s traffic had fallen, amid growing competition in the online discount market. The research by iCrossing using traffic data from Hitwise, Google and Alexa, found that traffic had peaked in April and May and then dropped.