Check out the companies making headlines after the bell Thursday:
Shares of firearms manufacturer Smith & Wesson jumped about 5 percent after it reported adjusted earnings of 32 cents a share, beating estimates by 10 cents, on $148 million in revenue, which also beat expectations. The company issued strong second-quarter revenue and earnings guidance.
Videogame and consumer-electronics retailer GameStop handed in better-than-expected second-quarter results, with adjusted earnings of 31 cents a share on $1.76 billion in sales. For the current quarter, GameStop said it expects to earn between 53 cents and 60 cents a share, compared with Street projections of 59 cents a share. The stock inched up about 2 percent.
Freeport-McMoRan shares surged about 19 percent after investor Carl Icahn reported a stake in the gold mining company and called its shares undervalued. Icahn said he intends to talk with the company about its capital structure and possible ways to curtail high-cost production operations.
Software designer Autodesk tumbled about 7 percent after it beat earnings estimates, on an adjusted basis, but missed sales forecasts. The company said it expects to earn between 5 and 10 cents a share for the current quarter, which was far below Wall Street's estimates of 23 cents a share. Autodesk's revenue outlook was weak as well.
The stocks of videogame maker Activision Blizzard and airline operator United Continental Holdings will soon become a part of the S&P 500, replacing Pall and Hospira, soon to be acquired by Pfizer. The swap between Activision and Pall, which is being acquired by Danaher, will take place at the close of trading on Friday. The United-Hospira transaction will occur on Sept. 2. Shares of United and Activision were both up about 7 percent in extended trading.
Apparel retailer Aeropostale saw its shares tumble about 1 percent after it reported quarterly results and said comparable-store sales decreased 8 percent.
Splunk, a data analytics firm, saw its shares rise about 3 percent after the company beat on the top and bottom lines and issued strong revenue guidance.
Ulta Salon, Cosmetics & Fragrance shares were up about 4 percent after the beauty products retailer reported earnings and revenue.