The top after-market NYSE gainers Tuesday were Newfield Exploration, Penn Virginia Corp, Western Refining, McClatchy and USG Corp. The top after-market NYSE losers were Kosmos Energy Ltd, Global Payments, Spectra Energy Partners, Heckmann Corp and Active Network Inc.

Gainers

Newfield Exploration Co. (NYSE:NFX) shares climbed 7.24 percent to $23.70 in post-market trading. The company announced Tuesday a significant natural gas discovery on the Block SK 310 Production Sharing Contract area, located 50 miles offshore Sarawak in approximately 250 feet of water.

Penn Virginia Corp. (NYSE:PVA) shares surged 3.59 percent to $4.04 in post-market trading. The company stock plunged nearly 3.5 percent in regular trading.

Western Refining Inc. (NYSE:WNR) shares gained 2.51 percent to $33.31 in post-market trading. The company stock tumbled more than 7 percent in regular trading.

McClatchy Co. (NYSE:MNI) shares advanced 2.47 percent to $2.61 in post-market trading. The stock has a 52-week low of $1.50, a 52-week high of $3.46 and $219.02 million in market capitalization.

USG Corp. (NYSE:USG) shares advanced 2.28 percent to $26.00 in post-market trading. The stock has a 52-week low of $13.12, a 52-week high of $30.97 and $2.68 billion in market capitalization.

Losers

Kosmos Energy Ltd. (NYSE:KOS) shares tumbled 10.55 percent to $10.00 in post-market trading. The stock has a 52-week low of $8.19, a 52-week high of $13.70 and $4.34 billion in market capitalization.

Global Payments Inc. (NYSE:GPN) shares plunged 6.45 percent to $45.85 in post-market trading. The company reported third quarter net profit of $58.5 million or $0.75 a share compared to $57.9 million or $0.73 per share in the same period last year. Quarterly revenue rose 8 percent to $578.7 million compared to $533.5 million last year but missed Reuters' estimate of $580.28 million.

Spectra Energy Partners L.P. (NYSE:SEP) shares declined 3.63 percent to $37.41 in post-market trading. The company announced that it has commenced an underwritten public offering of 4,500,000 of its common units representing limited partner interests.

Heckmann Corp. (NYSE:HEK) shares fell 1.68 percent to $4.10 in post-market trading. The stock has a 52-week low of $2.60, a 52-week high of $5.14 and $1.11 billion in market capitalization.

Active Network Inc. (NYSE:ACTV) shares declined 1.65 percent to $4.01 in post-market trading. The company stock surged more than 3 percent in regular trading.

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