Mattress Firm - The mattress retailer provided an updated full-year revenue guidance of between $1.01 billion and $1.03 billion, falling short of expectations for $1.04 billion. Shares plunged in extended-hours trading. (Click here for after-hours quote.)

JBHunt - The trucking and transportation company posted earnings of 67 cents a share, in line with expectations. But revenue missed expectations, sending shares lower in extended-hours trading. (Click here for after-hours quote.)

Agilent - The electronics manufacturer said it will buy AT4 wireless' Test Systems Business, but financial details of the deal were not disclosed. The acquisition is expected to be completed by early August. Shares edged higher in extended-hours trading. (Click here for after-hours quote.)

Life Technologies - The biotech company acquired privately held genomics company Navigenics, but financial terms were not disclosed. Shares edged higher in extended-hours trading. (Click here for after-hours quote.)

—By CNBC’s JeeYeon Park (Follow JeeYeon on Twitter: @JeeYeonParkCNBC )

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