The top after-market NYSE gainers Monday were Krispy Kreme, Qihoo 360, Sturm, Ruger & Co, Northern Tier and AmeriGas Partners. The top after-market NYSE losers were Celanese Corp, Atlas Resource, NeoPhotonics, SandRidge Energy and Ann Inc.

Gainers

Krispy Kreme Doughnuts, Inc. (KKD) shares climbed 11.67 percent to $8.42 in post-market trading. Its third quarter adjusted net profit rose to $0.12 per share from $0.07 per share in the same period last year and also topped Reuters estimate of $0.08 per share. The company currently expects fiscal 2013 adjusted earnings to be in a range of $0.44 to $0.47 per share, up from its prior estimate of $0.36 to $0.42 per share and above analysts' estimate of $0.43 per share.

Qihoo 360 Technology Co. Ltd. (QIHU) shares surged 4.98 percent to $24.88 in post-market trading. Its third quarter net profit surged to $12.93 million or $0.11 per ADS from $10.90 million or $0.09 per ADS in the same period last year.

Sturm, Ruger & Co, Inc. (RGR) shares gained 4.96 percent to $51.25 in post-market trading. The company announced Monday that its Board of Directors voted to declare a special dividend of $4.50 per share on the Company’s issued and outstanding shares of common stock, payable on Dec. 21, 2012, to shareholders of record as of Dec. 7, 2012.

Northern Tier Energy LP (NTI) shares gained 3.36 percent to $22 in post-market trading. The stock has a 52-week low of $13.00, a 52-week high of $25.80 and $1.96 billion in market capitalization.

AmeriGas Partners LP (APU) shares rose 2.47 percent to $40.53 in post-market trading. The stock has a 52-week low of $37.00, a 52-week high of $46.46 and $3.67 billion in market capitalization.

Losers

Celanese Corp. (CE) shares plunged 3.44 percent to $38.57 in post-market trading. The company stock surged more than 3.5 percent in regular trading.

Atlas Resource Partners, L.P. (ARP) declined 2.74 percent to $23.40 in post-market trading. The company announced Monday that it has commenced an underwritten public offering of 6,800,000 common units representing limited partner interests.

NeoPhotonics Corp. (NPTN) shares fell 2.87 percent to $5.17 in post-market trading.

SandRidge Energy Inc. (SD) shares fell 2.58 percent to $5.46 in post-market trading. The company announced Monday that its board of directors has unanimously adopted a stockholder rights plan and declared a dividend of one right on each outstanding share of SandRidge's common stock.

Ann Inc. (ANN) shares declined 2.83 percent to $33 in post-market trading. The stock has a 52-week low of $21.74, a 52-week high of $39.78 and $1.61 billion in market capitalization.