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.
Encore Bancshares Inc. (EBTX US) surged 35 percent, the most since going public in 2007, to $20.19. The Houston-based bank surged as Cadence Bancorp agreed to acquire the company for $20.62 per share or about $250 million.
Harvest Natural Resources Inc. (HNR US) rallied 23 percent, the most since June 2007, to $7.70. The Houston-based oil and natural-gas company said it’s in talks to sell its 32 percent stake in Petrodelta SA.
Medidata Solutions Inc. (MDSO US) advanced 15 percent, the most since June 2009, to $23.97. The provider of clinical data management software forecast first-quarter sales of $48.5 million at least, beating the average analyst estimate of $47.9 million in a Bloomberg survey.
Monster Worldwide Inc. (MWW US) rose 11 percent to $8.32 for the biggest gain in the Russell 1000 Index. The online recruiting service hired Stone Key Partners LLC and Bank of America Corp.’s Merrill Lynch to help it review strategic alternatives.
Nutrisystem Inc. (NTRI US) tumbled 11 percent to $10.58, the lowest price since May 2005. The provider of prepared meals to help clients lose weight forecast annual earnings per share of no more than 55 cents, falling short of the average analyst projection of 92 cents a share, data compiled by Bloomberg show.
OmniVision Technologies Inc. (OVTI US) rose 8.4 percent, the most since Feb. 16, to $17.16. The primary supplier of camera sensors for Apple Inc.’s (AAPL US) iPhone 4S was upgraded to outperform from neutral at Robert W. Baird & Co., which cited research showing the company may be a supplier of sensors for Apple’s iPad3.
Oncothyreon Inc. (ONTY US) plunged 40 percent to $5.07 for the biggest retreat in the Russell 2000 Index. The developer of cancer treatments fell after partner Merck KGaA (MRK GY) said experimental lung-cancer drug Stimuvax remains a high-risk project.
Quanex Building Products (NX US) dropped 7 percent, the most since Nov. 9, to $15.48. The producer of building materials reported a first quarter adjusted loss of 12 cents a share, wider than the average analyst estimated loss of 3 cents a share.
Shuffle Master Inc. (SHFL US) rose 10 percent to $16.05, the highest price since October 2007. The maker of casino roulette-chip sorters and card shufflers reported first-quarter revenue of $56.1 million, beating the average analyst estimate of $50.5 million.
Skullcandy Inc. (SKUL US) slumped 8.3 percent to $13.60 and dropped 11 percent earlier, the most intraday since Aug. 18. The maker of headphones said Chief Financial Officer Mitch Edwards is resigning, effective April 1.
VeriFone Systems Inc. (PAY US) gained 7.9 percent to $50.24, the highest price since May 10. The largest maker of credit-card terminals forecast 2012 earnings may be as much as $2.66 a share excluding some items, compared with the average analyst projection of $2.60 a share.
Zeltiq Aesthetics Inc. (ZLTQ US) tumbled 34 percent, the most since it went public in October, to $7.36. The Pleasanton, California-based maker of fat-reduction technology gave a forecast of 2012 sales that trailed analysts’ estimates.