The top after-market NYSE gainers on Monday were: BlackRock International, AMR Corp, SuccessFactors, Community Health Systems and A.H. Belo Corp. The top after-market NYSE losers were: STR Holdings, STR Holdings, AGL Resources, Vaalco Energy and GNC Holdings.

Gainers:

BlackRock International Ltd. (NYSE:BGY) shares climbed 11.11 per cent to $8.50 in aftermarket trading sessions. The stock has a 52-week low of $7.01, a 52-week high of $10.99 and $841.41 million in market capitalization.

AMR Corp. (NYSE:AMR) shares surged 8.27 per cent to $2.75 in post-market trading sessions. The company stock plunged more than 6 per cent in regular trading sessions.

SuccessFactors, Inc. (NYSE:SFSF) shares gained 7.28 per cent to $27.99 in post-market trading sessions after raising third quarter earnings outlook. For the third quarter, the company currently expects revenue to be in a range of $93 million to $95 million compared to its earlier estimation of $83 million to $84 million and analyst’s estimation of $83.62 million.

Community Health Systems, Inc. (NYSE:CYH) shares surged 5.15 per cent to $19.79 in post-market trading sessions. The stock has a 52-week low of $14.61, a 52-week high of $42.50 and $1.75 billion in market capitalization.

A.H. Belo Corp (NYSE:AHC) shares gained 4.71 per cent to $5.21 in post-market trading sessions. The company stock plunged more than 6 per cent in regular trading sessions.

Losers:

STR Holdings, Inc. (NYSE:STRI) shares slumped 13.94 per cent to $7.47 in post-market trading sessions as the company lowered its third quarter earnings estimates. For the third quarter, the company currently expects earnings to be in a range of $0.01 to $0.02 per share compared to its earlier estimation of $0.12 to $0.16 per share.

Ingram Micro Inc. (NYSE:IM) shares plunged 12.93 per cent to $16.30 in aftermarket trading sessions after lowering its third quarter earnings outlook.

AGL Resources, Inc. (NYSE:AGL) shares plunged 9.4 per cent to $37.01 in post-market trading sessions after lowering its full year earnings guidance. For the fiscal 2011, the company currently expects earnings to be in a range of $2.90 to $3.00 per share compared to its earlier estimation of $3.10 to $3.20 per share and analysts estimate of $3.12 per share.

Vaalco Energy Inc. (NYSE:EGY) shares plunged 8.94 per cent to $5.50 in aftermarket trading sessions. The stock has a 52-week low of $4.57, a 52-week high of $8.40 and $344.53 million in market capitalization.

GNC Holdings, Inc. (NYSE:GNC) shares declined 6.36 per cent to $20.60 in aftermarket trading sessions.