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.
Alcoa Inc. (AA US) fell 7 percent to $8.90 for the second-biggest retreat in the Dow Jones Industrial Average. The largest U.S. aluminum producer had its share-price estimate cut to $17 from $22 by JPMorgan Chase & Co., which said the metal’s prices will be lower than expected in the fourth quarter and next year.
Amedisys Inc. (AMED US) slid 9.6 percent to $13.40. LHC Group Inc. (LHCG US) lost 8.3 percent to $15.64. Gentiva Health Services Inc. (GTIV US) plunged 33 percent to $3.68. A Senate Finance Committee report found the home-care providers made added visits to Medicare patients to trigger federal bonuses.
AMR Corp. (AMR US) sank 33 percent, the most since March 2003, to $1.98. The parent of American Airlines slumped on concern U.S. is nearing a return to recession and that the carrier may be forced to seek bankruptcy protection. Andy Backover, a spokesman, said the company had no immediate comment on bankruptcy speculation.
Arch Coal Inc. (ACI US) slid 9.3 percent to $13.22, the lowest price since April 2009. The St. Louis-based coal miner cut its forecast for 2011 adjusted earnings to no more than $1.40 a share, from a previous prediction of at least $1.75. Analysts had estimated adjusted profit $2.01 a share, on average.
Other coal companies also retreated. Consol Energy Inc. (CNX US) declined 6.6 percent to $31.70. Patriot Coal Corp. (PCX US) tumbled 15 percent to $7.17.
Bank of America Corp. (BAC US) slipped 9.6 percent, the most in the Dow average, to $5.53. The largest U.S. bank by assets said that access to its online accounts was slower or halted for a second consecutive weekday because of heavy customer traffic. Company spokeswoman Tara Burke denied rumors that the slowness was the result of hacking.
Eastman Kodak Co. (EK US) surged 72 percent, the most in the Russell 2000 Index, to $1.34. The unprofitable 131-year-old camera maker said it had no intention of filing for bankruptcy, after three people with direct knowledge of the matter told Bloomberg News the company was weighing options including a bankruptcy filing to expedite the sale of patents.
Emergent Biosolutions Inc. (EBS US) climbed 11 percent, the most since May 26, to $17.13. The maker of drugs to fight bioterrorism said it will supply 44.75 million doses of its BioThrax anthrax vaccine to the U.S. government over the next years for a total value of as much as $1.25 billion.
Genworth Financial Inc. (GNW US) lost 7.8 percent to $5.29 in the biggest decline since Sept. 22. The mortgage guarantor and life insurer sold its Medicare supplement business to Aetna Inc. (AET US) for $276 million. Aetna fell 5.5 percent to $34.33.
Medicines Co. (MDCO US) climbed 12 percent, the most since September 2010, to $16.60. The maker of intravenous heart medicines reached a settlement with Teva Pharmaceutical Industries Ltd. (TEVA US) in which the Israeli generic drugmaker agreed to admit that two patents asserted by Medicines in the lawsuits are valid, Medicines said in a statement.
Micron Technology Inc. (MU US) fell the most in the Standard & Poor’s 500 Index, erasing 14 percent to $4.33. The U.S. maker of computer-memory chips may face a “largely negative” verdict this week with regards to the antitrust lawsuit by Rambus Inc. (RMBS US) against chipmakers, Lazard Capital Markets wrote in a note to clients.
Pharmaceutical Product Development Inc. (PPDI US) jumped 26 percent to $32.28 for the biggest increase in the Russell 1000 Index. The clinical research company agreed to be bought by Carlyle Group and Hellman & Friedman for $3.9 billion in cash, or $33.25 a share.
Popular Inc. (BPOP US) sank 19 percent, the most since April 2009, to $1.21. The biggest bank in Puerto Rico is is unlikely to begin discussing a Troubled Asset Relief Program repayment with regulators until the second half of 2012, Brett Scheiner, FBR Capital Markets Corp. analyst, said.
Sangamo BioSciences Inc. (SGMO US) slumped 30 percent, the second-biggest decline in the Russell 2000 Index, to $3.04. The Richmond, California-based company said it will discontinue development of a drug for diabetic neuropathy after the medicine, SB-509, wasn’t proven better than a placebo in phase II clinical tests.
VirnetX Holding Corp. (VHC US) dropped 17 percent to $12.38, the lowest price since March 11. The U.S. Patent and Trademark Office ordered a reexamination of the developer of instant-messaging and Internet-calling software’s patent for “Agile Network Protocol for Secure Communications with Assured System Availability.” Apple Inc. filed a reexamination request for the patent on July 11.
Wolverine World Wide Inc. (WWW US) jumped 4.1 percent, the most since Sept. 7, to $34.62. The shoemaker lifted its forecast for earnings in 2011 to as much as $2.52 a share from no more than $2.50, beating the average analyst estimate of $2.49.
Yahoo! Inc. (YHOO US) advanced 2.7 percent, the most in the S&P 500, to $13.53. The most-visited U.S. Web portal struck a partnership with ABC News as China’s Alibaba Group Holding Ltd. said it may be interested in acquiring Yahoo.