Take a look at some of Friday's midday movers:

Online social media companies fell including LinkedIn ,Zynga ,Sina and Groupon as Facebook opened. Zynga shares were halted on a single-stock circuit breaker.

Pfizer - The stock fell after the pharmaceutical company said it recently recalled more than 650 thousand bottles of Advil liquid-gels in March due to the potential for a strong odor in the product. The company said the recall wasn’t at the consumer level.

Winnebago rose after receiving an unsolicited buyout offer from North Street Capital for $321.5 million or $11 a share. But it said it hasn’t received enough information to deem the offer credible and urged shareholders not to take any action.

Gold stocks moved higher including Goldcorp ; NewmontMining ,Barrick Gold ; and AngloGold for the second straight as gold continued to rebound .

Schnizter Steel fell after providing downbeat guidance for its 3rd quarter due to higher costs for raw materials and freights.

Brown Shoes jumped on better than expected first quarter earnings as warm weather fueled higher sales of running shoes . The retailer also raised its 2012 outlook.

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