Shares of the following companies had unusual moves in U.S. trading. Prices are as of 4 p.m. in New York. Stock symbols are in parentheses.
U.S. airlines declined as crude oil rallied to the highest intraday price since October 2008. US Airways Group Inc. (LCC US) lost 3.7 percent to $7.13. Continental Airlines Inc. (CAL US) declined 3.9 percent to $21.15. American Airlines parent AMR Corp. (AMR US) fell 2 percent to $8.85.
Homebuilders gained after an index of sales of previously owned homes unexpectedly rose in February, signaling government efforts to support the market will start to pay off. Pulte Group Inc. (PHM US) rose 2.9 percent to $11.44. Lennar Corp. (LEN US) advanced 2.5 percent to $17.56. D.R. Horton Inc. (DHI US) climbed 0.6 percent to $12.59.
Arena Resources Inc. (ARD US) rose 7.2 percent, the most since May 18, to $36.71. SandRidge Energy Inc. (SD US) agreed to pay $1.55 billion for Arena. The purchase will make SandRidge one of the largest producers of West Texas conventional oil and gas. SandRidge fell 3.4 percent to $7.58.
Brush Engineered Materials Inc. (BW US) added 15 percent, the most since March 2009, to $26.15. The engineered materials company raised its 2010 sales forecast to $1.2 billion to $1.3 billion, above analyst estimates of $1.09 billion.
Cree Inc. (CREE US) jumped 10 percent to $77.63, the highest price since June 2000. The maker of energy-efficient lighting products was raised to "buy" from "neutral" at UBS, which also increased its share price estimate $92 from $60.
Harley-Davidson Inc. (HOG US) advanced 11 percent to $31.37, the highest price since October 2008. The motorcycle maker's price target was raised to $36 from $32 at RBC Capital.
International Game Technology (IGT US) rose 4.8 percent to 19.47, the highest price since Jan. 26. The casino gaming systems maker said it reached a four-year deal with Sun International Ltd. for 1,000 of its machines.
Keryx Biopharmaceuticals Inc. (KERX US) surged 22 percent to $3.35, the highest price since March 2008. The company's drug perifosine received a fast-track designation from the Food and Drug Administration for treatment of advanced colorectal cancer. It already has fast-track status related to some types of multiple myeloma.
Microvision Inc. (MVIS US) added 19 percent, the most since June 5, to $3.58. The developer of ultra-miniature projection display products said it has received an $8.5 million purchase order for its new engine.
NGP Capital Resources Co. (NGPC US) fell 7.3 percent, the most since Sept. 29, to $7.70. The energy business-development company was cut to "market perform" from "outperform" at Raymond James.
Reliance Steel & Aluminum Co. (RS US) rose 7.8 percent to $54.96, the highest price since August 2008. The largest American metal-warehousing company may gain 60 percent or more as the U.S. economy recovers and demand for steel and aluminum rises, boosting revenue and profit, Barron's reported.
STR Holdings Inc. (STRI US) declined 5.4 percent, the most since Dec. 8, to $21.38. The solar-panel parts maker announced a proposed secondary offering of 6.5 million shares.
Symyx Technologies Inc. (SMMX US) leapt 22 percent to $5.46 for the second-biggest gain in the Russell 2000. The provider of software and databases for laboratories announced a merger with Accelrys Inc. (ACCL US). Accelrys shares rose 7.9 percent to $7.01.
Tesoro Corp. (TSO US) fell 5.4 percent to $13.61, the biggest decline in the Standard & Poor's 500 Index. A chemical explosion killed five workers at the company's Anacortes, Washington, plant on April 2. The blast triggered the second federal investigation in six months of Tesoro, the biggest refiner on the U.S. West Coast.
Washington Post Co. (WPO US) rose 8.6 percent to $483 for the third-biggest gain in the S&P 500. The company's shares may be worth as much as $900 each based on the valuation of the company's Kaplan for-profit education unit, cable-television business, television stations and namesake newspaper, Barron's reported, without citing anyone.
Zions Bancorporation (ZION US) added 6.1 percent to $23.21, the highest price since January 2009. The Salt Lake City-based lender was raised to "hold" from "sell" at Collins Stewart and Sandler O'Neill. D.A. Davidson rated it a new "buy" with a share-price estimate of $28.
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