The top after-market NYSE gainers Thursday were SAIC Inc, Domtar Corp, McEwen Mining, Freescale Semiconductor and Crane Co. The top after-market NYSE losers were Accretive Health, Gerdau SA, Quicksilver Resources, American Eagle Outfitters and CoreLogic, Inc.

Gainers

SAIC Inc. (SAI) shares rallied 10.08 percent to $13.00 in post-market trading. The company announced Thursday that its Board of Directors, following a recently completed comprehensive strategic review, had authorized the management to pursue a plan to separate it into two independent, publicly traded companies and was expected to occur in the latter half of next fiscal year.

Domtar Corp. (UFS) shares surged 3.17 percent to $73.80 in pre-market trading. The company stock plunged more than 3 percent in regular trading.

McEwen Mining Inc. (MUX) shares gained 2.96 percent to $3.82 in post-market trading. The stock has a 52-week low of $1.96, a 52-week high of $6.49 and $995.37 million in market capitalization.

Freescale Semiconductor Ltd. (FSL) shares advanced 2.83 percent to $10.16 in post-market trading.

Crane Co. (CR) shares rose 2.41 percent to $38.71 in post-market trading. The stock has a 52-week low of $33.23, a 52-week high of $51.48 and $2.17 billion in market capitalization.

Losers

Accretive Health, Inc. (AH) shares plunged 2.05 percent to $11.68 in post-market trading. The company stock climbed more than 10 percent in regular trading.

Gerdau SA (GGB) shares declined 1.68 percent to $8.78 in post-market trading. The company stock was upgraded to a "neutral" rating from an "underperform" rating at Zacks.

Quicksilver Resources Inc. (KWK) shares fell 1.49 percent to $3.43 in post-market trading after plunging more than 3 percent in regular trading.

American Eagle Outfitters (AEO) shares declined 1.30 percent to $22.01 in post-market trading. The stock has a 52-week low of $10.00, a 52-week high of $22.49 and $4.38 billion in market capitalization.

CoreLogic, Inc. (CLGX) shares declined 1.27 percent to $24.12 in post-market trading. The stock has a 52-week low of $9.98, a 52-week high of $24.86 and $2.57 billion in market capitalization.