The top after-market NYSE gainers Friday were Sprint Nextel Corp, Belo Corp, Natural Grocers by Vitamin Cottage, Green Dot Corp and Sauer-Danfoss Inc. The top after-market NYSE losers were Tata Motors Ltd, Owens & Minor, Infoblox and Graphic Packaging Holding Co.

Gainers

Sprint Nextel Corp. (S) shares surged 4.64 percent to $4.51 in post-market trading after climbing more than 6 percent in regular trading.

Belo Corp. (BLC) shares surged 3.81 percent to $7.09 in post-market trading. The company stock climbed nearly 9 percent in regular trading after announcing second quarter earnings. Net profit was $25.9 million or $0.24 per share, up from $18.1 million or $0.17 per share in the same quarter last year and also topped Reuters' estimate of $0.19 per share.

Natural Grocers by Vitamin Cottage, Inc. (NGVC) shares gained 2.91 percent to $20.48 in post-market trading.

Green Dot Corp. (GDOT) shares gained 2.43 percent to $9.28 in post-market trading. The company stock slumped 61 percent after lowering its fiscal 2012 earnings guidance. The company currently expects that its fiscal 2012 adjusted net profit will be in the range of $1.29 to $1.32 per share on revenues of $534 to $543 million, down from its prior estimate of $1.65 to $1.70 per share on adjusted revenue of $582 to $601 million. The company stock was also downgraded to "hold" from a "buy" rating at Deutsche Bank and Jefferies Group.

Sauer-Danfoss Inc. (SHS) shares advanced 1.99 percent to $37.96 in post-market trading. The stock has a 52-week low of $25.60, a 52-week high of $56.10 and $1.80 billion in market capitalization.

Losers

Tata Motors Ltd. (TTM) shares plunged 3.71 percent to $19.20 in post-market trading. The stock has a 52-week low of $14.33, a 52-week high of $30.63 and $63.28 billion in market capitalization.

Owens & Minor, Inc. (OMI) shares plunged 3.27 percent to $27.81 in post-market trading. The stock has a 52-week low of $25.87, a 52-week high of $32.00 and $1.83 billion in market capitalization.

Infoblox Inc. (BLOX) shares fell 2.97 percent to $21.32 in post-market trading. The company stock climbed more than 8 percent in regular trading.

Graphic Packaging Holding Co. (GPK) shares fell 2.94 percent to $5.61 in post-market trading. The company stock surged more than 3.5 percent in regular trading.