Shares of the following companies had unusual moves in U.S. trading. Stock symbols are in parentheses and prices are as of 4 p.m. in New York.
Air Transport Services Group Inc. (ATSG US) increased 16 percent, the most since April 2011, to $5.65. The aircraft leasing and cargo transportation provider said its second quarter earnings were 19 cents a share, beating the average analyst estimate by 16 percent.
Alpha Natural Resources Inc. (ANR US) fell 17 percent, the most since December 2008, to $33.24. The coal company, which bought Massey Energy Co. for $7.1 billion in June, reported a second-quarter loss of $56.4 million on takeover-related costs.
Clearwire Corp. (CLWR US) lost 29 percent to $1.76, the lowest price since its initial public offering in March 2007. The money-losing wireless broadband provider reported its net loss widened to $168.7 million, or $1.01 per share, from $125.9 million, or 61 cents.
Dendreon Corp. (DNDN US) plunged 67 percent to $11.69 for the biggest retreat in the Russell 1000 Index. The drugmaker withdrew its sales estimates for 2011 and announced job cuts because of lower-than-expected growth in the use of prostate-cancer treatment Provenge.
DirecTV (DTV US) slid 5.7 percent, the most since February 2009, to $46.63. The largest satellite-TV provider added a net 26,000 subscribers in the U.S. during the second quarter, missing analysts’ estimates, while growth in the average revenue per user slowed to 3 percent, a sign that the cost of competition “materializes,” according to Nomura Holdings Inc.
Emdeon Inc. (EM US) rose 13 percent, the most in the Russell 1000 Index, to $18.35. The provider of health-care revenue and payment cycle management solutions agreed to be bought by Blackstone Group LP (BX US) for $19 a share, or $3 billion. Blackstone fell 11 percent to $13.72.
Entropic Communications Inc. (ENTR US) tumbled 38 percent, the most since its initial public offering in December 2007, to $4.14. The designer of digital home networking semiconductors posted second-quarter earnings that missed its April forecast. Revenue fell short of analyst projections, according to data compiled by Bloomberg.
Gap Inc. (GPS US) decreased 12 percent to $16.98, the lowest price since August 2010. The retailer said July same-store sales fell 5 percent, compared with analysts’ estimates for a decline of 0.6 percent.
Huntsman Corp. (HUN US) fell 31 percent, the most since December 2008, to $12.50. The chemical maker reported second-quarter net income of 47 cents a share, missing analysts’ estimates.
Leap Wireless International Inc. (LEAP US) declined 34 percent to $6.65, the lowest price since at least August 2004. The pay-as-you-go mobile-phone carrier reported a net loss of 85 cents a share in the second quarter, wider than analysts estimated.
Rival MetroPCS Communications Inc. (PCS US) fell 9.4 percent to $9.31, the lowest price since September.
McDermott International Inc. (MDR US) dropped 27 percent, the most since November 2008, to $13.95. The offshore oil and gas contractor posted second-quarter profit excluding some items of 27 cents a share, missing the average analyst estimate by 14 percent, according to Bloomberg data.
MEMC Electronic Materials Inc. (WFR US) slid 14 percent to $6.02, the lowest price since October 2002. The second-largest U.S. manufacturer of polysilicon posted second-quarter earnings of 29 cents a share, six times the average analyst projection, Bloomberg data show.
PMI Group Inc. (PMI US) dropped 53 percent, the most since its IPO in April 1995, to 41 cents. The third-largest mortgage insurer posted its 16th straight unprofitable quarter and failed to meet regulators’ capital requirements.
Transocean Ltd. (RIG US) fell 8.6 percent, the most since June 1, to $53.98. The world’s largest offshore driller posted an 11th straight quarterly profit decline. Daily rental rates for the company’s vessels dropped as much as 26 percent during the second quarter because of competition from rival operators and an influx of newer rigs onto global drilling markets.
Walter Energy Inc. (WLT US) declined 30 percent, the most since at least 1995, to $77.89. The southern Appalachia producer of steelmaking coal reported second-quarter revenue of $766.7 million, missing the $931 million average estimate by analysts in a Bloomberg survey.
Web.com Group Inc. (WWWW US) soared 20 percent, the most in the Russell 2000 Index, to $10.37. The company that builds Web sites for small businesses said it is buying Network Solutions and expects the deal to add at least 20 percent to the consensus estimate of its 2012 earnings.
Zumiez Inc. (ZUMZ US) fell 20 percent, the most since July 2008, to $21.77. The retailer based in Everett, Washington, reported comparable sales for July that missed analysts’ estimates for first month since December.