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.
Activision Blizzard Inc. (ATVI US) slumped 6.5 percent, the most since Jan. 6, to $10.99. The largest video-game publisher said sales this quarter will be $725 million, excluding changes in deferred revenue. Analysts estimate sales of $914.5 million on average. The company forecast adjusted earnings of 8 cents a share, below the 12-cent average estimate.
Alphatec Holdings Inc. (ATEC US) fell the most in the Russell 2000 Index, plunging 46 percent to $2.39. The maker of medical devices reduced its full-year sales projection after second-quarter earnings missed analysts’ estimates.
American International Group Inc. (AIG US) added 2.6 percent to $40.93, the highest price since May 12. The insurer rescued by the U.S. said second-quarter operating profit rose 17 percent as results improved from U.S. life operations. AIG also said it may sell its $2.4 billion stake in American General Finance Inc.
American Public Education Inc. (APEI US) tumbled 32 percent to $29.96, the most intraday since it went public in November 2007. The operator of the American Military University scrapped its 2010 forecast, saying it will no longer provide annual projections.
Other for-profit schools also declined after BMO Capital Markets Corp. reduced the industry’s rating to “market perform” from “outperform,” citing the prospect of increased oversight.” DeVry Inc. (DV US) slipped 6.1 percent to $47.83. Education Management Corp. (EDMC US) dropped 8 percent to $13.04. Career Education Corp. (CECO US) decreased 6.2 percent to $20.55. Strayer Education Inc. (STRA US) fell 1.6 percent to $216.59. Grand Canyon Education Inc. (LOPE US) declined 9.4 percent to $20.81.
Assured Guaranty Ltd. (AGO US) gained the most in the Russell 1000 Index, rallying 15 percent to $18.44. The bond insurance company backed by billionaire Wilbur Ross reported net income for the second quarter of $203.5 million, reversing a year-earlier loss.
ATP Oil & Gas Corp. (ATPG US) dropped 16 percent, the most since June 1, to $11.08. The petroleum and gas producer in the Gulf of Mexico said its second-quarter net loss was $82.9 million, compared with a net loss of $4.4 million a year earlier.
Autodesk Inc. (ADSK US) fell 5.1 percent to $28.77 for the biggest decline since June 29. The maker of software used in bridge design and the special effects in the movie “Avatar” was cut to “hold” from “buy” at Jefferies & Co. The 12-month share-price estimate is $31.
Blue Nile Inc. (NILE US) declined 4.8 percent to $45.26, the lowest price since July 2. The online diamond and jewelry retailer reported second-quarter profit of 19 cents a share, trailing the average analyst estimate of 23 cents in a Bloomberg survey.
CEC Entertainment Inc. (CEC US) dropped 5.6 percent, the most since July 31, to $32.60. The owner of Chuck E. Cheese’s restaurants reduced its full-year forecast after second-quarter earnings trailed analysts’ estimates.
Crocs Inc. (CROX US) climbed 11 percent, the most since March 17, to $13.95. The maker of plastic clogs forecast third-quarter profit of at least 22 cents a share, beating the average analyst estimate of 15 cents in a Bloomberg survey.
Harman International Industries Inc. (HAR US) declined 12 percent to $29.88 for the biggest retreat in the Standard & Poor’s 500 Index. The maker of audio systems for homes and vehicles posted fourth-quarter profit excluding some items of 30 cents a share, trailing the average analyst estimate by 6.3 percent, according to Bloomberg data.
Kraft Foods Inc. (KFT US) rose the most in the Dow Jones Industrial Average, advancing 2.4 percent to $30.36. The maker of Oreo cookies and Maxwell House coffee posted second-quarter profit excluding some items of 60 cents a share, beating the 52-cent average estimate from analysts in a Bloomberg survey.
LMI Aerospace Inc. (LMIA US) slumped 15 percent, the most since March 2009, to $15.27. The maker of aluminum and alloy components used by the aerospace industry lowered its sales forecast for the year to no more than $242 million, missing the average analyst estimate of $245 million in a Bloomberg survey.
Nanometrics Inc. (NANO US) jumped 25 percent, the most since November 2008, to $12.33. The semiconductor-gear maker reported second-quarter profit of 51 cents a share, beating the average analyst estimate by 82 percent, according to Bloomberg data.
Overstock.com Inc. (OSTK US) slumped 17 percent, the most since July 2008, to $16.78. The online discount retailer posted a second-quarter loss of 6 cents a share, compared with the average estimate of a profit of 2 cents a share by analysts in a Bloomberg survey.
PerkinElmer Inc. (PKI US) rose the most in the S&P 500, climbing 11 percent to $22.29. The provider of equipment for genetic screening and drug research boosted its full-year forecast after second-quarter profit beat analysts’ estimates.
PharMerica Corp. (PMC US) plunged 25 percent to $9.60, the lowest since it began trading. The Louisville, Kentucky-based pharmaceutical services firm forecast fiscal-year revenue of no more than $1.81 billion, less than the average analyst estimate of $1.83 billion in a Bloomberg survey.
PowerSecure International Inc. (POWR US) slumped 12 percent, the most since March 2009, to $9.75. The provider of lighting and electrical systems was cut to “hold” from “buy” at Roth Capital Partners LLC.
Washington Post Co. (WPO US) dropped 7.6 percent to $377.56 for the second-biggest loss in the S&P 500. The newspaper publisher said proposed rules from the Department of Education may have “a material effect” on its Kaplan for-profit education unit.