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.
Staffing companies gained after a Labor Department report showed a drop in applications for unemployment benefits. Monster Worldwide Inc. (MWW US) rose 9.6 percent to $22.36 for the biggest gain in the Standard & Poor’s 500 Index. Robert Half International Inc. (RHI US) increased 3.7 percent to $28.13 while Kforce Inc. (KFRC US) increased 2.9 percent to $15.43.
Amazon.com Inc. (AMZN US) advanced 5.4 percent to $177.33, the highest price since it went public in May 1997. The Web retailer is “the best play off the secular growth in online retail” and the stock is worthy of “a material market premium,” analyst Mark S. Mahaney of Citigroup Inc. said in a note.
Anacor Pharmaceuticals Inc. (ANAC US) rose 1.8 percent to $5.09 on the first day of trading. Palo Alto, California-based developer of small-molecule therapeutics raised $60 million in an initial public offering after originally seeking as much as $84.6 million.
Armstrong World Industries Inc. (AWI US) advanced 2.7 percent to $48.11 for its biggest gain since Nov. 5. The maker of floors, ceilings and cabinets said it obtained a $1.05 billion senior secured credit facility and declared a special cash dividend of $13.74 a share. Standard & Poor’s and Moody’s lowered their credit ratings on the company as a result of the recapitalization.
Boeing Co. (BA US) rose the most in the Dow Jones Industrial Average, rallying 2.9 percent to $65.51. The world’s largest aerospace company may be able to deliver the 787 Dreamliner jet faster than expected after suspending test flights to investigate why one of the planes caught fire, Cowen & Co. said in a note. The stock may rebound on the company’s next 787 update, Cowen said.
CBOE Holdings Inc. (CBOE US) fell the second-most in the Russell 1000 Index, sliding 3.3 percent to $23.87. The owner of the world’s largest equity derivatives market said it purchased shares from former seatholders of the Chicago Board Options Exchange in a tender offer.
Cree Inc. (CREE US) gained 10 percent to $64.45 for the second-biggest increase in the Russell 1000 Index. The maker of energy-efficient lighting products was added to Morgan Keegan Inc.’s focus list.
Dynamex Inc. (DDMX US) jumped 13 percent to $23.78 for its biggest gain since Oct. 4. The provider of same-day delivery services said it received a takeover offer of $23.50 a share that its board of directors viewed as a “superior proposal.”
Guess? Inc. (GES US) had the biggest advance in the Russell 1000 Index, climbing 11 percent to $50.12. The clothing designer and retailer raised its 2011 earnings forecast to at least $3.02 per share, higher than the average analyst estimate of $2.93, according to a Bloomberg survey.
Inhibitex Inc. (INHX US) surged 14 percent, the most since Sept. 3, to $2.74. The developer of antibody-based treatments said it intends to sell $20 million shares.
Lynas Corp. (LYSCF US) advanced 16 percent, the most since September 2009, to $1.56. The Australian rare earths developer and Japan’s Sojitz Corp. signed a supply deal that will speed up the company’s plan to double capacity and also secure supply for Japan after China slashed exports.
Mattson Technology Inc. (MTSN US) rose 5.5 percent to $2.88 for its biggest gain since Nov. 10. The Fremont, California-based maker of equipment for semiconductors made a NT$567 million ($19 million) sale to Taiwan Semiconductor Manufacturing Co.
Oracle Corp. (ORCL US) added 2 percent to $22.74 for its biggest gain since Oct. 28. SAP AG (SAP GR), the world’s largest maker of business application software, must pay $1.3 billion to Oracle for copyright infringement by a now-defunct software maintenance unit, a federal jury in California decided.
SanDisk Corp. (SNDK US) gained 4.8 percent to $45.01, the highest price cine Aug. 10. Demand for the biggest maker of flash-memory cards’ Nand flash storage should continue to grow and products will keep improving, UBS AG equity analyst Uche Orji said in a note to clients.
Synopsys Inc. (SNPS US) advanced 2.5 percent, the most since Aug. 19, to $25.71. The semiconductor designer was raised to “overweight” from “neutral” at JPMorgan Chase & Co. Sterling Auty, the analyst, said in a report the company’s cash flow may increase more than 30 percent in 2010 and 16 percent in 2011.
Syswin Inc. (SYSW US) fell 11 percent to $6.20 on the first day of trading. The Beijing-based real-estate agency sold 9.6 million American depositary receipts at $7 each after cutting the initial public offering from 12 million ADRs at $9.25 to $11.25.
Tiffany & Co. (TIF US) rose 5.3 percent to $61.33, the highest price since it went public in May 1987. The world’s second-largest luxury jewelry retailer reported third-quarter earnings excluding some items of 46 cents a share, beating the average analyst estimate of 36 cents, as sales rose globally.
Tutor Perini Co. (TPC US) slid 3.8 percent to $19.23, the lowest price since Aug. 5. The building construction company said it sold 4.5 million shares of common stock at $19.50 a share.