Chairman's exit sends Freeport-McMoRan shares down

Editor's note: Due to holiday production deadlines, this report does not include developments from Thursday trading.

Executive shake-up: Freeport-McMoRan fell 10 percent Monday to $6.84 following news that James R. Moffett, the mining company's executive chairman and co-founder, is stepping down. Plunging commodity prices have led to mass layoffs across the entire industry. The move follows the recent revelation that activist investor Carl Icahn has taken a huge stake in the company. The stock closed Wednesday at $6.77.

Sick leave: Valeant Pharmaceuticals lost 10 percent Monday, to $102.40 after the company announced that CEO J. Michael Pearson is taking a medical leave of absence. Pearson was hospitalized with pneumonia last week. Three executives will take over for Pearson during his absence. The company's stock closed at $102.33 Wednesday.

Discouraging result: Chimerix plunged 81.4 percent Monday, to $6.65 after the biotechnology company's oral antiviral drug for infections associated with stem cell transplants failed in a late-stage study. The stock closed Wednesday at $8.35.

Icahn wins: Bridgestone said late Tuesday that it is bowing out of the bidding war for Pep Boys, noting it won't make a counteroffer to top a roughly $1 billion bid from activist investor Carl Icahn. Pep Boys stock dropped 3 percent on the news Wednesday, to $18.39.

Being wooed: Fairchild Semiconductor International rose 4 percent Wednesday, to $20.75 after the company said the previous day that it has received an unsolicited offer to buy its business by an undisclosed bidder. The roughly $2.46 billion offer tops Fairchild's existing deal with ON Semiconductor.