Today’s midday gainers are Mallinckrodt PLC (NYSE:MNK), InvenSense Inc (NYSE:INVN) and Gold Fields Limited (ADR) (NYSE:GFI). The midday losers are WPX Energy Inc (NYSE:WPX), Dean Foods Co (NYSE:DF) and American Capital Ltd. (NASDAQ:ACAS).

chart_1 (8) Dean foods

Mallinckrodt Soars Off Acquisition Deal

Up +10.03%, the midday gainer of the day is Mallinckrodt PLC (NYSE:MNK). The surge comes on the heels an announcement that the pharmaceutical company will acquire Cadence Pharmaceuticals (NASDAQ:CADX) as part of a $1.3 billion deal. A week ago, Mallinckrodt announced Q1 2014 per-share earnings of $0.88, beating consensus estimates. With 5.64 million shares as of September, MNK composes 1.6% of John Paulson’s portfolio.

Next up is hardware provider Invensense Inc (NYSE:INVN), the stock price of which increased +9.65% after Robert W. Baird upgraded its price target from $20.00 to 23.00. Yesterday evening, the company announced it had entered into a cross-licensing agreement with STMicroelectronics (NASDAQ:STM) after a patent war that had halted several projects.

Last up this Tuesday is gold explorer and producer Gold Fields Limited (ADR) (NYSE:GFI), up +8.67%. Today, the company declared the group had produced 21% more gold than in the previous quarter. Both Ray Dalio and Paulson are stakeholders here.

Dean Foods falls short in Q4

Falling -9.75%, our midday loser is WPX Energy Inc (NYSE:WPX). The oil and gas exploration and production giant announced today that its full year earnings would be hurt by $1.4 billion in pretax impairment charges. Both David Einhorn and Leon Cooperman have allocations in this company – WPX composing 1.6% of Einhorn’s fund and 0.62% of that of Cooperman.

Coming in at a close second is Dean Foods Co (NYSE:DF), down -9.04%. A stock market pick for both Thomas Steyer and David Tepper, Dean reported Q4 earnings falling short of expectations. Most of its financial metrics declined steeply despite high dairy prices – an indication that the company sold much less than its competitors.

Rounding out today’s list is American Capital Ltd. (NASDAQ:ACAS), which dipped -7.15%. A venture capital firm specialized in buyouts, American Capital also posted disappointing earnings for Q4. It missed EPS expectations by $0.10, and its quarterly revenue was down -34.4% year-over-year. With 3.78 million shares, ACAS comprises 0.34% of Paulson’s portfolio.