He's being replaced by Executive Chairman Eric Lefkofsky and Vice Chairman Ted Leonisis. They will serve as co-CEOs until they find a permanent replacement.
Here is Lefkofsky's statment: On behalf of the entire Groupon Board, I want to thank Andrew for his leadership, his creativity and his deep loyalty to Groupon. As a founder, Andrew helped invent the daily deals space, leading Groupon to become one of the fastest growing companies in history. Groupon will continue to invest in growth, and we are confident that with our deep management team and market-leading position, the company is well positioned for the future.
And if I remember correctly, Eric Lefkofsky was one of the investors who cashed out ~$1billion (!) of his Groupon shares during one of their last VC rounds. I'm surprised they were able to do that, but so many people were killing themselves to be a part of the deal that Eric was able to push this slimy deal through. How any rational VC allows early investors to do that is beyond me...
Nothing against the guy (I have no experience with him) but that deal just smelled rotten. So I'm not convinced that these two people are going to be particularly effective replacements/stand-ins.
Here is Lefkofsky's statment: On behalf of the entire Groupon Board, I want to thank Andrew for his leadership, his creativity and his deep loyalty to Groupon. As a founder, Andrew helped invent the daily deals space, leading Groupon to become one of the fastest growing companies in history. Groupon will continue to invest in growth, and we are confident that with our deep management team and market-leading position, the company is well positioned for the future.
Source: http://techcrunch.com/2013/02/28/ceo-andrew-mason-replaced-b...