The top after-market NYSE gainers Friday were American Vanguard, GrafTech International, Sibanye Gold, Millennial Media and Renren Inc. The top after-market NYSE losers were EPAM Systems, Roundy's, Annie's and Lithia Motors.

Gainers

American Vanguard Corp. (NYSE:AV) shares climbed 8.38 percent to $31.03 in post-market trading. The company’s stock slumped more than 7.5 percent in regular trading.

GrafTech International Ltd. (NYSE:GTI) shares surged 6.03 percent to $7.39 in post-market trading. The company’s stock was downgraded to a “neutral” rating from an “overweight” rating at JPMorgan Wednesday.

Sibanye Gold Ltd. (NYSE:SBGL) shares surged 4.47 percent to $6.12 in post-market trading. The stock has a 52-week low of $5.64, a 52-week high of $6.36 and $1.07 billion in market capitalization.

Millennial Media, Inc. (NYSE:MM) shares gained 2.42 percent to $9.30 in post-market trading. The stock has a 52-week low of $8.78, a 52-week high of $27.90 and $718.98 million in market capitalization.

Renren Inc. (NYSE:RENN) shares advanced 2.41 percent to $2.98 in post-market trading. The stock has a 52-week low of $2.85, a 52-week high of $7.87 and $1.08 billion in market capitalization.

Losers

EPAM Systems Inc. (NYSE:EPAM) shares plunged 6.55 percent to $20.98 in post-market trading. The company’s stock climbed 7 percent in regular trading.

Roundy's, Inc. (NYSE:RNDY) shares plunged 4.50 percent to $5.73 in post-market trading. The stock has a 52-week low of $3.69, a 52-week high of $12.50 and $273.92 million in market capitalization.

Annie's, Inc. (NYSE:BNNY) shares plunged 3.27 percent to $40.88 in post-market trading. The company announced Friday the filing of a registration statement on Form S-1 with the U.S. Securities and Exchange Commission with respect to a proposed underwritten offering of 3.5 million shares of common stock to be sold exclusively by affiliates of Solera Capital.

Lithia Motors, Inc. (NYSE:LAD) shares declined 3.32 percent to $41.10 in post-market trading. The stock has a 52-week low of $21.45, a 52-week high of $44.80 and $1.09 billion in market capitalization.

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