AIG, Alphatec, Ambac Financial, Myriad, NYSE, Peabody: U.S. Equity Movers

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) had the third-biggest gain in the Dow Jones Industrial Average, climbing 1.3 percent to $14.57. The largest U.S. aluminum producer is due to report first-quarter earnings after the close of trading today. Analysts, on average expected the company to earn 9 cents a share, according to a Bloomberg survey.

Alphatec Holdings Inc. (ATEC US) had the second-biggest drop in the Russell 2000 Index, sliding 8.3 percent to $5.84. The maker of medical devices said it will delay the introduction in the U.S. of OsseoScrew, an expandable pedicle screw designed for bone requiring additional fixation, because the Food and Drug Administration requires additional data. Separately, HealthpointCapital Partners LP offered to sell 8 million shares, cutting its stake to 12.5 percent, according to a regulatory filing.

Ambac Financial Group Inc. (ABK US) rallied 104 percent, the most ever, to $2.25. The bond insurer soared for a second day after reporting fourth-quarter net income of $558.1 million, reflecting a tax benefit and unrealized gains on derivatives.

American International Group Inc. (AIG US) rose 8.1 percent to $41.22, the highest price since Oct. 22. Treasury officials are discussing ways to extricate the U.S. from its stake of almost 80 percent in the bailed-out insurer, the Wall Street Journal reported, citing unidentified people familiar with the situation.

ArvinMeritor Inc. (ARM US) rose 6.3 percent to $15.02, the highest price since September 2008. The maker of parts for cars and trucks was added to the “Conviction Buy” list at Goldman Sachs Group Inc., which also raised its share-price estimate to $19 from $15.

Boots & Coots Inc. (WEL US) surged 26 percent, the most since October 2003, to $2.95. The company that fights oil-well fires agreed to be bought by Halliburton Co. (HAL US) for about $240.4 million in stock and cash, or $3 per share.

Bruker Corp. (BRKR US) climbed 3 percent to $14.92, the highest price since September 2008. The maker of laboratory instruments may rise as much as 33 percent during the next year as biotechnology research by governments, universities and corporations expands, Barron’s reported, citing Jose Haresco, an analyst at Brean Murray Carret & Co. in New York.

California Pizza Kitchen Inc. (CPKI US) increased 1.6 percent to $21.07, the highest price since July 2007. The restaurant chain said it is reviewing options including a possible sale and reported preliminary first-quarter earnings that beat its forecast.

     Caterpillar Inc. (CAT US) had the biggest gain in the Dow Jones Industrial Average, rising 2.2 percent to $66.73. The world’s largest maker of bulldozers and excavators was raised to “outperform” from “neutral” at Robert W. Baird & Co., which cited improving fundamentals.

Ciena Corp. (CIEN US) climbed 7.6 percent to $17.49, the highest price since September 2008. The maker of fiber-optic network gear was raised to “buy” from “underperform” at Bank of America Corp.

Clean Energy Fuels Corp. (CLNE US) dropped 7.6 percent, the most since Sept. 1, to $19.82. The company co-founded by billionaire T. Boone Pickens to provide natural gas for motor vehicles may fall as much as 30 percent because of a potential warrant exercise by Pickens by 2012, Barron’s reported, without citing anyone.

Double-Take Software Inc. (DBTK US) gained 20 percent, the most since April 2008, to $10.44. The maker of software to protect data said it received “indications of interest” to acquire the company.

DynCorp International Inc. (DCP US) surged 48 percent to $17.41 for the third-biggest gain in the Russell 2000 Index. The defense contractor that’s helped trained Iraqi police agreed to be acquired by Cerberus Capital Management LP for about $1.5 billion, including the assumption of debt.

Expedia Inc. (EXPE US) rose 2.5 percent to $25.18, the first gain in four days. The online travel agency was upgraded to “overweight” from “neutral” by Piper Jaffray Cos.

Javelin Pharmaceuticals Inc. (JAV US) had the second- biggest gain in the Russell 2000 Index, soaring 60 percent to $2.15. The developer of pain medications said it received an offer from Hospira, Inc. (HSP US) to buy the company at $2.20 a share, ending a merger agreement by Myriad Pharmaceuticals Inc. (MYRX US) Myriad increased 10 percent to $5.

Mirant Corp. (MIR US) jumped 18 percent to $12.68 for the second-biggest advance in the Russell 1000 Index. The Atlanta- based electricity producer and RRI Energy Inc. (RRI US) will combine their companies in a $1.6 billion stock transaction to cut costs and take advantage of an expected recovery in power prices, the two companies said yesterday.

RRI Energy climbed 15 percent to $4.53.

NYSE Euronext (NYX US) gained 5.9 percent, the most since July 13, to $32.31. The operator of the biggest U.S. stock exchange had its 2010 earnings estimate increased to $2.38 a share from $2.25 a share at JPMorgan Chase & Co. because of “higher growth potential in derivatives volume.”

    Palm Inc. (PALM US) rose 17 percent to $6.04, the highest price since March 3. The creator of the Pre smartphone is seeking bids for the company as early as this week, according to three people familiar with the situation.

Peabody Energy Corp. (BTU US) rose 3.6 percent, the most since Feb. 16, to $48.01. The world’s biggest coal producer is in preliminary talks with Coal India Ltd. over “long-term” supply agreements and potential cooperative ventures, Vic Svec, vice president of corporate communications, said today in an e- mailed statement.

St. Jude Medical Inc. (STJ US) rose 3 percent to $42.46, the highest price since October 2008. The maker of devices to treat irregular heartbeats was upgraded to “neutral” from “sell” at Goldman Sachs Group Inc. and to “buy” from “hold” by Jefferies Group Inc.

    Texas Instruments Inc. (TXN US) gained 3 percent to $25.69, the highest price since Jan. 11. The chipmaker was raised to “outperform” from “neutral” at Credit Suisse Group AG, which said that robust demand should support revenue growth.

Under Armour Inc. (UA US) rose 2.1 percent to $32.95, thie highest price since Oct. 26. The maker of polyester workout gear was raised to “overweight” from “neutral” at Piper Jaffray Cos. The 12-month share-price estimate is $41.

Vertex Pharmaceuticals Inc. (VRTX US) fell 1.1 percent to $39.26, the lowest price since Feb. 16. The drugmaker was downgraded to “neutral” from “overweight” at JPMorgan. The 9-month share-price estimate is $43.

To contact the reporter on this story: Lu Wang in New York at lwang8@bloomberg.net

Press spacebar to pause and continue. Press esc to stop.

Bloomberg reserves the right to remove comments but is under no obligation to do so, or to explain individual moderation decisions.

Please enable JavaScript to view the comments powered by Disqus.