Market Insider

After-hours buzz: Nike, SeaWorld, Mattress Firm & more

Check out the companies making headlines after the bell Thursday:

Pro: Buy Nike on pullback
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Pro: Buy Nike on pullback

SeaWorld Entertainment - The theme park operator's stock edged higher after the company named Joel Manby as president and CEO. SeaWorld's shares rose about 3 percent after the announcement.

Nike - The sportswear retailer topped earnings estimates, but sales came in below expectations as it struggles with the negative impacts of a stronger dollar. Shares rose about 1 percent after the announcement.

Mattress Firm - The retailer's shares rose about 3 percent in after-hours trading after it reported adjusted fourth-quarter earnings of 41 cents a share on $598 in revenue. Wall Street had expected the company to report adjusted profit of 47 cents a share on $563 million in revenue.

Prothena - The drug developer's shares rose a much as 40 percent after it reported positive results from an early stage study of its Parkinson's drug.

AK Steel - The company said it expects a first-quarter loss of between 23 cents and 28 cents a share, versus Street expectations of a loss of a penny a share. The stock fell more than 6 percent after the announcement

- The company reported a fourth-quarter loss of 26 cents a share on $308 million in revenue, beating projections for a loss of 28 cents a share on sales of $305 million. The stock spiked 10 in extended trading.