Stocks to Watch: GRPN, A, MM & More

Check out which companies are making headlines after-the-bell Monday:

Groupon - The deal-of-the-day website reported earningsof 2 cents a share on revenue of $559 million, edging past expectations for 1 cent a share on sales of $531 million.

In addition, the firm handed in a better-than-expected quarterly revenue guidance, boosting shares in extended-hours trading, after surging more than 18 percent in the regular trading session. (Click here for after-hours quote.)

Agilent -The electronic equipment maker reported earnings of 78 cents a share, excluding one-time items, on sales of $1.73 billion. Analysts had expected the company to post earnings of 73 cents a share on revenue of $1.71 billion. Shares were higher in extended-hours trading. (Click here for after-hours quote.)

Millenial Media - The mobile advertising and data company posted a loss of 5 cents a share, excluding one-time items, versus expectations for a loss of 7 cents a share. Revenue to $32.9 million, ahead of estimates of $30 million. Also, the mobile advertising and data company forecast handed in quarterly guidance that topped expectations. (Click here for after-hours quote.) (*Correction: An earlier version of the story said MM posted a wider-than-expected loss.)

Widely-followed hedge fund manager David Tepper's Appaloosa Management disclosed new stakes in Citigroup , Bank of America , Google and GM . In addition, the firm nearly tripled its stake in Apple , while doubling its position in Microsoft . (Click here for after-hours quotes.)

Adobe Systems - The firm announced it is expanding its board of directors from nine members to 12. (Click here for after-hours quote.)

OPNT - The tech firm posted earnings of 21 cents a share and revenue of $45 million, both in line with Wall Street estimates. Meanwhile, the firm raised its dividend, sending shares higher in extended-hours trading. (Click here for after-hours quote.)

Cornerstone OnDemand - The software company posted a loss of 10 cents a share, in line with expectations, and revenue that met estimates. Shares of the firm declined in extended-hours trading. (Click here for after-hours quote.)

Lantronix - The computer technology manufacturer announced the resignation of its chairman of the board Thomas Wittenschlaeger. (Click here for after-hours quote.)

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