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.
Arbitron Inc. (ARB US) climbed 5.1 percent, the most since Jan. 3, to $37.21. The provider of audience ratings for U.S. radio stations forecast sales that beat analysts’ estimates and said it plans to buy back as much as $100 million in stock.
Charles River Laboratories International Inc. (CRL US) gained 3.9 percent to $35.23, the highest price since Aug. 3. The seller of mice and rats used in laboratory experiments reported earnings that beat analyst estimates.
Cloud Peak Energy Inc. (CLD US) fell 6.2 percent to $17.04, the lowest price since Oct. 4. The coal mining company was lowered to underweight from equalweight at Barclays Capital, meaning the firm expects the shares to perform worse than average among industry peers over the next 12 months. The price estimate is $17.
Energy Conversion Devices Inc. (ENER US) plunged 80 percent, the most since at least 1983, to 29 cents. The U.S. solar manufacturer that suspended production last year filed for bankruptcy with plans to sell off its solar panel unit.
Fidelity National Information Services Inc. (FIS US) rallied 7 percent to $31.04, the biggest gain in the Standard and Poor’s 500 Index. The payment-processor reported fourth-quarter earnings excluding some items of 66 cents a share, beating the average analyst estimate of 65 cents.
First Solar Inc. (FSLR US) fell 6 percent to $39.21 for the second-biggest retreat in the S&P 500. The biggest maker of thin-film solar panels may “have the most near term downside risk” under a German proposal to cut subsidies that is likely to be “worse than expected,” Deutsche Bank AG said in a note.
GT Advanced Technologies Inc. (GTAT US), a U.S. maker of solar manufacturing equipment, declined 1.5 percent to $9.08. LDK Solar Co. (LDK US) fell 12 percent to $5.55. MEMC Electronic Materials Inc. (WFR US) sank 11 percent to $4.72.
Golar LNG Ltd. (GLNG US) gained 5.5 percent, the most since Jan. 19, to $46.68. The owner of liquefied natural gas carriers led by Norway-born billionaire John Fredriksen will buy at least two more of the ships as demand for the fuel rises as much as 10 percent a year.
Goodyear Tire & Rubber Co. (GT US) declined 5.2 percent, the most since Jan. 10, to $13.25. The largest U.S. tiremaker reported fourth-quarter profit that was less than analysts’ estimates as the number of tires sold declined 5 percent.
Hospira Inc. (HSP US) rallied 6.1 percent, the most since Sept. 23, to $36.30. The maker of generic injectable drugs said a factory cited for manufacturing problems had reopened and was near previous production levels.
LivePerson Inc. (LPSN US) surged 19 percent to $14.96, the highest price since it went public in 2000. The customer service software maker reported fourth-quarter earnings that beat analysts’ estimates.
Masco Corp. (MAS US) dropped the most in the S&P 500, erasing 12 percent to $11.63. The home improvement and building products maker reported a fourth-quarter loss from continuing operations of 9 cents a share, wider than the average analyst estimate of a loss of 2 cents.
Michael Kors Holdings Ltd. (KORS US) surged 27 percent, the most since it went public in December, to $42.85. The clothing company reported third-quarter earnings excluding some items of 28 cents a share, beating the 11 cent average estimate of analysts.
On Assignment Inc. (ASGN US) jumped 14 percent to $13.67, the highest price since July 2002. The staffing company said earnings in the fourth quarter were 20 cents a share, beating the average analyst estimate of 16 cents.
Rackspace Hosting Inc. (RAX US) rallied 13 percent to $55.45 for the second-biggest increase in the Russell 1000 Index. The biggest competitor to Amazon.com Inc. in the market for Web-based data centers said net income jumped 85 percent to $25 million, beating analyst estimates.
Seattle Genetics Inc. (SGEN US) sank 5.4 percent, the most since Nov. 9, to $17.94. The maker of the Hodgkin lymphoma drug Adcetris didn’t provide a 2012 sales forecast with its fourth-quarter earnings report.
Syntroleum Corp. (SYNM US) rose 18 percent, the most since Nov. 7, to $1.30. The company’s Dynamic Fuels LLC venture with Tyson Foods Inc. (TSN US) agreed to supply renewable diesel to Norfolk Southern Corp. (NSC US).
Ultra Clean Holdings Inc. (UCTT US) advanced 13 percent, the most since Oct. 27, to $8.85. The supplier of equipment to semiconductor makers said first-quarter earnings will be at least 15 cents a share, beating the average analyst estimate of 9 cents.
Valspar Corp. (VAL US) gained 4.1 percent to $45.82, the highest price since at least 1980. The producer of non-automotive industrial paint said first-quarter earnings were 62 cents a share, excluding some items, beating the average analyst estimate of 48 cents.
Yahoo! Inc. (YHOO US) sank 4.7 percent, the most since Oct. 31, to $15.37. The U.S. web portal’s talks concerning a possible sale of its Asian assets have hit an impasse, AllThingsDigital reported, citing sources close to the situation.
Zipcar Inc. (ZIP US) dropped 14 percent to $13.84 for the biggest decline in the Russell 2000 Index. The company, which rents cars by the hour or day, forecast first-quarter profit that was lower than analysts’ estimates as it boosts marketing and other expenses to expand in Europe.