Check out which companies are making headlines after the bell Tuesday:
Yahoo - The Internet company posted earnings of 35 cents a share, excluding one-time items, on revenue of $1.07 billion against expectations for 30 cents a share on sales of $1.08 billion. It also handed in disappointing current-quarter guidance, sending shares lower in extended-hours trading.
CSX - The railroad operator posted earnings of 52 cents a share on revenue of $3.1 billion, beating expectations for 47 cents a share on sales of $3.02 billion. Shares rallied in extended-hours trading.
Dell - In a letter, the tech giant's special committee urged its shareholders to vote for the buyout offer of $13.65 a share and criticized billionaire investor Carl Icahn's latest proposal. Shares edged higher in extended-hours trading.
Packaging Corp of America - The containerboard manufacturer posted earnings of 71 cents a share on sales of $800 million, exceeding expectations for 63 cents a share on revenue of $770 million. In addition, the company handed in current-quarter earnings guidance that edged past projections, sending shares higher in extended-hours trading.
Realogy - The real estate and relocation services provider said that it expects to post second-quarter earnings of between $1.03 a share and $1.09 a share on revenue of between $1.53 billion and $1.54 billion, against current expectations for 70 cents a share on sales of $1.47 billion. The company is slated to post results on July 24. Shares climbed in extended-hours trading.
Separately, Apollo Global Management announced an offering of its remaining 25.1 million-share stake in Realogy. The deal is valued at nearly $1.24 billion.
Gardner Denver - Shareholders approved a definitive agreement to be acquired by KKR. The companies expect the merger to be completed in late July or early August 2013. Shares of the industrial compressor company were largely unchanged in extended-hours trading.
United Rental - The equipment rental company posted earnings of $1.12 a share on revenue of $1.21 billion, versus expectations for $1.01 a share on sales of $1.23 billion. In addition, the company reaffirmed its full-year outlook. Shares declined in extended-hours trading.
Zagg - The consumer electronics accessories maker said it expects to post sales of $51 million in the second quarter, missing expectations for $59 million. In addition, the company cut its full-year revenue guidance to between $245 million and $252 million, disappointing forecasts for $274 million. Shares plunged sharply after being temporarily halted in extended-hours trading.