The U.K. Office of Fair Trading has been looking into Groupon's British unit since July and expanded the probe after receiving a complaint from the country's advertising watchdog.
"Given Groupon's track record, we have serious concerns about its ability to adhere to the advertising code," the Advertising Standards Authority said in a statement. "It is in the public interest that we refer the matter to the OFT."
Groupon, based in Chicago, raised $700 million on Nov. 3, selling 35 million shares at $20 each, the biggest IPO by a U.S. internet company since Google first sold shares in 2004. Groupon rose 8.3% yesterday to $18.95 in New York trading. "
We are constantly evolving [the] business process to ensure customers receive the best possible experience at the highest standards," a Groupon spokesperson said in an e-mailed statement. "We are cooperating fully with the OFT to ensure that the rights of consumers are protected."