The top after-market NYSE gainers Thursday were Tempur-pedic International, iSoftStone Holdings, Qihoo 360 Technology, MGIC Investment and ResMed Inc. The top after-market NYSE losers were Ship Finance International, Spirit Aerosystems Holdings, Molycorp, American Water Works Co and AOL Inc.

Gainers

Tempur-pedic International Inc. (NYSE:TPX) shares rallied 14.21 percent to $43.80 in pre-market trading. Its fourth quarter net profit declined to $23.5 million or $0.39 per share from $56.3 million or $0.84 per share in the same period last year. The adjusted profit was $36.4 million or $0.60 per share, above the analysts’ estimate of $0.55 per share.

iSoftStone Holdings Ltd. (NYSE:ISS) shares surged 3.70 percent to $5.62 in pre-market trading. The stock has a 52-week low of $3.68, a 52-week high of $11.04 and $308.00 million in market capitalization.

Qihoo 360 Technology Co. Ltd. (NYSE:QIHU) shares gained 2.92 percent to $32.63 in post-market trading. The company stock plunged nearly 3 percent in regular trading.

MGIC Investment Corp. (NYSE:MTG) shares rose 2.62 percent to $3.13 in post-market trading. The company stock slumped nearly 6 percent in regular trading.

ResMed Inc. (NYSE:RMD) shares advanced 2.49 percent to $46.60 in post-market trading. The company reported the second quarter net income of $77.9 million or $0.53 per share, up from $62.87 million or $0.42 per share in the same quarter last year and also topped Reuters’ estimate of $0.51 per share.

Losers

Ship Finance International Ltd. (NYSE:SFL) shares slumped 6.22 percent to $16.43 in post-market trading. The company announced Thursday that it intended to offer, subject to market and other conditions, $250 million aggregate principal amount of its Convertible Senior Notes due 2018.

Spirit Aerosystems Holdings Inc. (NYSE:SPR) shares fell 4.95 percent to $15.18 in post-market trading. The stock has a 52-week low of $13.96, a 52-week high of $26.00 and $2.92 billion in market capitalization.

Molycorp Inc. (NYSE:MCP) shares fell 2.69 percent to $6.88 in post-market trading after plunging more than 10 percent in regular trading.

American Water Works Co Inc. (NYSE:AWK) shares fell 2.59 percent to $37.59 in post-market trading. The company announced Thursday that it expected 2012 earnings per share from the continuing operations to be at the low-end of the previously announced range of $2.12 to $2.22, prior to taking into account its $7 million donation to the American Water Charitable Foundation.

AOL Inc. (NYSE:AOL) shares declined 2.44 percent to $30.05 in post-market trading. The stock has a 52-week low of $15.46, a 52-week high of $43.93 and $2.58 billion in market capitalization.