Weekly gainers for December 21, 2013 are LSI Corp (NASDAQ:LSI), KKR Financial Holdings LLC (NYSE:KFN), Avalon Rare Metals Inc (NYSEMKT:AVL) and weekly losers are Jabil Circuit, Inc. (NYSE:JBL), AVEO Pharmaceuticals, Inc. (NASDAQ:AVEO), Gold Fields Limited (NYSE:GFI).

LSI Corp

LSI Corp is this week’s top gainer

On the top of our weekly gainer list is LSI Corp (NASDAQ:LSI), the tech stock increased +37.66% to $10.96. Billionaire George Soros holds 4.3 million shares, composing 0.37% of his fund. The investor picked up 3.06 million shares during the second quarter, and increased its position by 1.3 million shares during last quarter at an average price of $7.05 per share.

Following LSI Corporation is KKR Financial Holdings LLC (NYSE:KFN), the financial stock shot up +30.69% to $12.27 during this week, since the company announced the signing of a definitive merger agreement where KKR will acquire KFN for $2.6 billion. This was a well-received news for Leon Cooperman who holds more than 15 million shares (2.35% of his holdings), purchased at an average price of $6.72 per share.

Third and last stock of our weekly gainer list is Avalon Rare Metals Inc (NYSEMKT:AVL) the mineral company rose +22.82% to $0.47 during last five days. As of September, Richard Chilton holds 661,000 shares, representing 0.02% of his fund. The investor paid an average price of $6.10.

Weekly Losers

The weekly top loser company this week is Jabil Circuit, Inc. (NYSE:JBL), the tech company dipped -14.87% to $16.10 during last week. According to the last 13F, Billionaire Ray Dalio bought 19,000 shares for $22.21 during last quarter.

The second stock in our weekly loser list is AVEO Pharmaceuticals, Inc. (NASDAQ:AVEO), the healthcare firm dropped -14.36%, hitting $1.69 this week. As of September Seth Klarman holds a 3.8 million shares position, composing 0.23% of his fund. The investor paid an average price of $15.22 per asset.

Last stock in our weekly list is Gold Fields Limited (NYSE:GFI), the gold company decreased -13.96% to $3.09. Billionaire John Paulson owns 6.5 million shares (0.19% of his fund) acquired for $6.44 per share. Another investor with a position in GFI is Ray Dalio who holds 373,000 shares, composing 0.01% of his holdings. Dalio paid an average price of $6.85 per asset.

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