Check out which companies are making headlines after the bell Monday:
Apple - The tech giant posted earnings of $8.26 a share on revenue of $37.5 billion, exceeding Wall Street projections for $7.96 a share on sales of $36.93 billion. Meanwhile, the company reported it sold 33.8 million iPhones and 4.6 million Macs in the quarter, topping estimates. But it sold 14.1 million iPads, lighter than expectations. In addition, the company handed in current-quarter gross margins that were below forecasts, sending shares lower in extended-hours trading.
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Herbalife - The nutrition and skin-care products company reported earnings of $1.41 a share, excluding one-time items, easily beating estimates for $1.14 a share, while revenue was in line with Wall Street expectations at $1.20 billion. In addition, the company boosted its full-year forecast and appointed Dr. Richard Carmona, former surgeon general, to its board. Shares rallied in extended-hours trading.
Hartford Financial - The financial services company reported earnings of $1.03 a share on revenue of $5.64 billion, outstripping estimates for 83 cents a share on sales of $4.87 billion. Shares rose in extended-hours trading.
General Growth Properties - The real estate investment trust posted earnings of 29 cents a share on revenue of $621 million, versus expectations for 27 cents a share on sales of $637 million. Shares were flat in extended-hours trading.
Seagate - The data storage company posted earnings of $1.29 a share, excluding one-time items, on sales of $3.49 billion, missing expectations for $1.30 a share on sales of $3.56 billion. In addition, the company handed in a lighter-than-expected current-quarter guidance, sending shares lower in extended-hours trading.
Michael Kors - The handbag and accessories maker will join the S&P 500 index, replacing NYSE Euronext. The change will take place after the close of trading on Friday. Shares of Michael Kors rallied in extended-hours trading, while NYSE Euronext slipped.
Riverbed Technology - The networking hardware company posted earnings of 26 cents a share, ex-items, beating expectations for 23 cents. But revenue was slightly below expectations at $265 million, versus $267 million. Shares jumped in extended-hours trading.
Nutrisystem - The weight-loss products maker posted earnings of 15 cents a share, excluding one-time items, on sales of $85 million, beating forecasts for 13 cents a share on revenue of $81 million. In addition, the company issued current-quarter guidance that were mostly in line with estimates. Shares spiked in extended-hours trading.
Plum Creek Timber - The largest private landowner announced a 14.1 million share offering through Goldman Sachs and JPMorgan. In addition, MWV announced a deal with Plum Creek to sell its U.S. forestlands. Shares declined in extended-hours trading.
PMC-Sierra - The fabless semiconductor company posted earnings of 10 cents a share, ex-items, in line with expectations, while revenue was slightly below estimates. But the company handed in current-quarter guidance that disappointed analysts, sending shares sharply lower in extended-hours trading.
Talisman - Billionaire investor Carl Icahn raised his stake in the oil and gas exploration to 6.96 percent, from 5.97 percent. Shares rose in extended-hours trading.
Gamestop - The videogame retailer was initiated with a "buy" rating at Stifel Nicolaus and a $65 price target. Shares ticked higher in extended-hours trading.
—By CNBC's JeeYeon Park (Follow JeeYeon on Twitter: @JeeYeonParkCNBC)
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