The one billionth Groupon has been sold

Daily deals service Groupon reached an important milestone: one billion sold.

The company announced Friday the one billionth Groupon was sold, a promotion at restaurant Pirrone's Pizzeria in St. Louis. The restaurant will receive $10,000 for selling the landmark Groupon.

"We’re thrilled and humbled to join the select group of brands and names in the billion-sold club,” said Groupon CEO Rich Williams in a statement Friday.

The company is hosting a sale to celebrate the one-billion milestone.

Shares of Groupon have been on the decline for more than a year, as the company shifted CEOs and pulled its service out of several countries. However, its stock has surged recently after Chinese e-commerce giant Alibaba revealed it claimed a stake in Groupon.

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