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What: Shares of United Online (UNKNOWN:UNTD.DL) have plunged today by as much as 12% after the company reported first-quarter earnings.

So what: Revenue in the first quarter added up to $247.4 million, topping the Street's forecast of $243.4 million. Adjusted earnings per share were $0.16, right on target with analysts' best guesses. The company is proceeding along its plan to spin off the FTD business as an independent, publicly traded company.

Now what: CEO Mark Goldston said he would be leaving the company following the spin-off after 14 years as CEO. That revelation has created substantial uncertainty for United Online and FTD, which could be rattling investors. The United Online board will be searching for a new CEO once the spin-off is complete, and FTD President Rob Apatoff will become FTD's CEO.

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