(For more market insights, including options activity, click on ; for the Day Ahead newsletter link.reuters.com/mex49s; for the Morning News Call newsletter, link.reuters.com/nex49s) U.S. stocks fell on Thursday afternoon, led by a sharp drop in biotech and momentum stocks. Investors were also reluctant to make big bets ahead of Friday's nonfarm payrolls report, when they will be looking for evidence that recent weather-related weakness in the economy has passed. The Dow Jones industrial average was down 0.12 percent at 16,553.22, the S&P 500 was down 0.24 percent at 1,886.33 and the Nasdaq Composite was down 1.13 percent at 4,228.20.
** TARENA INTERNATIONAL INC, $9.58, +6.44 pct
Shares of the provider of IT education in China rose as much as 20 percent in their market debut, underscoring the renewed interest in Chinese stocks among U.S. investors.
The Beijing-based company's IPO was priced at $9 per American depositary share. The shares opened at $9.86 and touched a high of $10.80 on the Nasdaq on Thursday.
** ANADARKO PETROLEUM CORP, $98.07, +13.42 pct
** TRONOX LTD, $24.89, +1.76 pct
Anadarko Petroleum and its Kerr-McGee unit will pay $5.15 billion to resolve environmental cleanup claims stemming from the 2009 bankruptcy of paint materials maker Tronox, the biggest environmental bankruptcy settlement on record.
Anadarko's potential liability has weighed on its shares since December, when U.S. Bankruptcy Judge Allan Gropper said Kerr-McGee, which Anadarko bought in 2006, acted "with intent to hinder" when it spun off its titanium dioxide unit Tronox a year earlier. At the time, Gropper said Anadarko should pay from $5.15 billion to more than $14 billion in cleanup costs.
** GOOGLE INC Class C, $566.8, -0.04 pct
** GOOGLE INC Class A, $568.44, +0.06 pct
The S&P 500 now consists of 501 stocks, as the index now includes both Google's Class A and Class C shares in the wake of the company's special dividend.
** LIBERTY MEDIA CORP, $130.46, -2.11 pct
** BARNES & NOBLE INC, $18.99, -14.11 pct
John Malone's Liberty Media is slashing its stake in Barnes & Noble by 90 percent, three years after it invested $204 million in the struggling U.S. bookstore chain and its then promising e-reader, the Nook.
** PANDORA MEDIA, $29.86, -5.03 pct
The streaming radio service provider said listener hours rose 14 percent to 1.71 billion in March. The company also said active listeners rose 8 percent to 75.3 million and the share of total U.S. radio listening for Pandora rose to 9.11 percent from 8.05 percent a year earlier.
** SGOCO GROUP LTD, $2.82, -29.15 pct
The Chinese flat-panel display maker reported a 63 percent fall in fourth-quarter profit and a 30 percent fall in revenue. The company said the significant growth in revenue a year earlier led to tough comparisons with the latest quarter.
** AMYRIS INC, $4.11, +1.99 pct
The renewable chemicals and fuels company said it would partner with German chemicals group BASF on a strain development program. Amyris will use its strain engineering technology to develop a microorganism capable of producing a target molecule.
** BG MEDICINE INC, $1.57, -18.23 pct
The diagnostic test maker said it will offer about 6.5 million shares at $1.55 each, at a discount of about 19.3 percent to its Wednesday close. The company expects to raise about $8.9 million in net proceeds to fund clinical development and for working capital.
** VENAXIS INC, $2.34, -13.65 pct
The diagnostic test maker's offering of about 8.3 million shares was priced at $2.40 each, a discount of about 11 percent to the stock's Wednesday close.
The company expects to raise net proceeds of about $18.4 million for working capital and to fund clinical development.
** MANTECH INTERNATIONAL CORP, $28.49, -6.44 pct
** PACWEST BANCORP, $46.81, +2.50 pct
S&P Dow Jones Indices said late on Wednesday that IT security services company ManTech would move to the S&P SmallCap 600 from the S&P MidCap 400 while PacWest Bancorp would take its place in the S&P MidCap 400 after the close of trading on April 7.
** E*TRADE FINANCIAL CORP, $22.115, -6.69 pct
** TD AMERITRADE HOLDING CORP, $32.09, -5.12 pct
** CHARLES SCHWAB CORP, $27.53, -1.33 pct
Shares of E*Trade and Ameritrade, both of whom do high-frequency trading (HFT), were down after rival Charles Schwab issued a statement against HFT, calling on U.S. regulators to impose high cancellation fees to discourage quote stuffing or even making HFT illegal.
HFT is practiced by many hedge funds, banks and proprietary firms using sophisticated computer programs to send high volumes of orders at near light speed, executing short-term trades to make markets or capitalize on price imbalances. HFT makes up more than half of all U.S. trading volume.
** CYTRX CORP, $3.89, +2.10 pct
The company said its experimental cancer drug raised the rate of survival two and a half times in mice suffering from glioblastoma multiforme (GBM) tumors, a common form of a malignant brain tumor.
** LIQUIDITY SERVICES INC, $18.34, -12.08 pct
The scrap goods auctioneer said it had withdrawn from bidding for a contract from the U.S. Defense Logistics Agency (DLA) calling the determined bidding level as "economically unsustainable".
The company said on Wednesday it was the apparent high bidder for the contract where it was to purchase, manage and sell non-rolling stock surplus assets of the U.S. Department of Defense.
** CATALYST PHARMACEUTICAL PARTNERS INC, $2.39, +8.14 pct
The drugmaker's offering of about 11.3 million shares was priced at $2.21 apiece, the same as the stock's close on Wednesday. The company expects net proceeds of $23.3 million to fund drug development and for general purposes.
** RPM INTERNATIONAL INC, $44.13, +4.65 pct
The specialty chemicals maker posted a profit in third quarter compared with a year-ago loss, helped by higher sales of its industrial chemical products.
The company also raised its full-year profit forecast to $2.10 to $2.15 per share from $2.05 to $2.10.
** VIVUS INC, $5.72, -7.44 pct
Piper Jaffray cut its rating on the drugmaker's stock to "underweight" from "neutral", according to Theflyonthewall.com.
** ON SEMICONDUCTOR CORP, $9.77, +2.84 pct
Brokerage Raymond James raised its price target on the power-management chip maker's stock to $11 from $9, saying the company's acquisition of Trusense Imaging Inc on Wednesday would help it gain market share in the image-sensor business. The brokerage also expects demand from mobile and automotive businesses to boost ON Semiconductor's revenue over the next two years. More than 15 million shares were traded on Thursday, double their 50-day trading average.
** RITE AID CORP, $6.5, +2.20 pct
** WALGREEN CO, $66.98, +0.95 pct
Rite Aid, a drugstore chain operator, reported a 0.7 percent rise in March same-store sales and a 3.5 percent rise in pharmacy same-store sales. Total drugstore sales rose 0.4 percent.
Walgreen reported an 8.9 percent increase in March pharmacy sales and 8 percent rise in comparable-store pharmacy sales.
** PLUG POWER INC, $7.55, +0.94 pct
** BALLARD POWER SYSTEMS INC, $4.46, -8.42 pct
Plug Power said it bought fuel-cell stack maker ReliOn Inc for about $4 million in stock, as the company looks to diversify its supplier base.
Canada's Ballard Power is currently Plug Power's exclusive supplier in North America and some European countries.
** EXACT SCIENCES CORP, $12.9799, -8.91 pct
The molecular diagnostics company said it will sell $125 million worth of shares to raise proceeds to fund clinical development and for working capital.
** CACI INTERNATIONAL INC, $71.43, -4.20 pct
The U.S. contractor lowered its revenue and profit forecast for 2014 due to reduced government spending and delays in contract awards for new business.
** BROADWIND ENERGY INC, $12.43, -7.65 pct
Two shareholders of the wind turbine towers maker sold 103,752 shares at a 4 percent discount to the stock's Wednesday's close of $13.46.
** PACIFIC ETHANOL INC, $15.48, -10.26 pct
The renewable fuel producer said it started an offering of 1.8 million shares at $16 per share, a discount of 7 percent to the stock's close on Wednesday. The company expects to use the proceeds of $28 million for interest payments.
** CTRIP.COM INTERNATIONAL LTD, $52.6775, +0.97 pct
The China-based travel services provider said its board authorized a new share repurchase program to buy American depositary shares of up to $600 million.
** PERRY ELLIS INTERNATIONAL INC, $14.78, +3.72 pct
The apparel company reported a higher-than-expected fourth-quarter profit helped by sales of certain apparel categories and rise in licensing income. The company also maintained its fiscal 2015 forecast.
** SEAWORLD ENTERTAINMENT INC, $29.76, -2.23 pct
The theme park and entertainment company said on Wednesday that it expects to report first-quarter attendance of about 3.05 million guests, down from 3.5 million a year earlier.
The company also said that an affiliate of The Blackstone Group LP would sell 15 million of the company's shares, of which SeaWorld would buy 1.75 million.
** KINDRED BIOSCIENCES INC, $18.14, -9.12 pct
The company, which makes drugs for pets, said it would offer 30 million shares at $18 each, a discount of 9.8 percent to the stock's closing on Wednesday. The company expects to raise $54 million for potential acquisitions and research and development.
** ACACIA RESEARCH CORP, $16.63, +1.96 pct
The company, which buys and licenses patent technologies, said its unit Cell and Network Selection LLC had resolved all disputes with Motorola Mobility LLC and Huawei Technologies Co Ltd.
** SCHNITZER STEEL INDUSTRIES INC, $29.1, +3.56 pct
The steel maker reported a better-than-expected adjusted profit in the second quarter, boosted by higher selling prices and cost cuts. Excluding items, it earned 13 cents per share, almost double the 7 cents analysts on average were expecting, according to Thomson Reuters I/B/E/S.
** VERSO PAPER CORP, $2.81, -6.95 pct
The U.S. Department of Justice has asked the coated paper maker for additional information regarding its proposed acquisition of NewPage Holdings Inc. (r.reuters.com/qyw28v)
** INVESCO LTD, $36.62, -2.81 pct
Investment group St James's Place (SJP) is transferring management of 7.7 billion pounds ($12.81 billion) of its assets from Invesco Perpetual. The changes do not affect Invesco's assets under management, though it will lose millions of pounds in annual management fees.
Neil Woodford, who will leave Invesco Perpetual to join Oakley Capital Management in May, will be allocated nearly half of the transfer. He has managed SJP funds since 2001.
** JINKOSOLAR HOLDING CO LTD, $30.75, -3.91 pct
The Chinese solar company said it received a loan of about $39 million from China Development Bank to finance two solar projects in the Xinjiang and Gansu provinces. (Compiled by Abhirup Roy in Bangalore; Editing by Savio D'Souza)