The top after-market NASDAQ stock market losers are: Semtech, Sequenom, ON Semiconductor, Ansys, rue21, TD Ameritrade Holding, Varian Semiconductor Equipment Associates, E*TRADE Financial, Compuware, SunPower, and Synopsys.

Semtech Corp. (SMTC) lost 7.87 percent to $22.14 in the after-hours trading. The company's third quarter adjusted profit was $30.9 million or 48 cents a share, up from $16.2 million or 27 cents a share last year. Revenue grew 63.8 percent to $123.1 million. Analysts had expected profit of 46 cents a share on revenue of $122.12 million.

Semtech expects fourth quarter adjusted profit of 39 cents to 43 cents a share and revenue of $110 million to $116 million. Analysts expect profit of 42 cents a share on revenue of $116.66 million.

Sequenom Inc. (SQNM) plunged 7.49 percent to $6.30 in the after-market session. The company said it plans to sell shares of its common stock in an underwritten public offering. Jefferies & Company, Inc. is acting as sole book-running manager and Lazard Capital Markets LLC and Piper Jaffray & Co. are acting as co-managers for the offering.

ON Semiconductor Corp. (ONNN) plummeted 6.28 percent to $8.14 in the after-hours trading.

Ansys, Inc. (ANSS) fell 4.63 percent to $48.44 in the after-market session.

rue21, Inc. (RUE) dropped 4.20 percent to $29.67 in the after-hours trading. The company's third quarter profit was $7.1 million or 29 cents a share, up from $6 million or 26 cents a share last year. Sales rose 19.5 percent to $163.9 million. Analysts had expected profit of 27 cents a share on revenue of $162.67 million. Comparable store sales rose 1.8 percent.

rue21 expects fourth quarter earnings of 40 cents to 43 cents a share and sales growth of 19 percent to 21 percent. Analysts expect profit of 42 cents a share on revenue of $185.46 million, with sales growth of 19.40 percent.

rue21 raised its fiscal 2010 earnings outlook to range of $1.17 to $1.20 a share from previous forecast of $1.14 to $1.19 a share, while analysts project $1.19 a share.

TD Ameritrade Holding Corp. (AMTD) tumbled 3.81 percent to $16.72 in the after-market session.

Varian Semiconductor Equipment Associates Inc. (VSEA) declined 3.60 percent to $31.57 in the after-hours trading.

E*TRADE Financial Corp. (ETFC) decreased 3.59 percent to $14.73 in the after-market session.

Compuware Corp. (CPWR) moved down 3.23 percent to $10.29 in the after-hours trading.

SunPower Corp. (SPWRA) fell 3.19 percent to $11.68 in the after-market session.

Synopsys Inc. (SNPS) declined 1.36 percent to $26.15 in the after-hours trading. The company's fourth quarter adjusted profit was $59.9 million or 39 cents a share, up from $49.5 million or 33 cents a share last year. Revenue rose to $375.5 million from $338.3 million. Analysts had expected profit of 39 cents a share on revenue of $355.58 million.

Synopsys expects first quarter adjusted profit of 38 cents to 41 cents a share and revenue of $360 million to $368 million. Analysts expect profit of 41 cents a share on revenue fo $362.80 million. The company expects fiscal 2011 adjusted profit of $1.67 to $1.77 a share and revenue of $1.5 billion to $1.525 billion. Street expects profit of $1.75 a share on revenue of $1.47 billion for 2011.

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